Most often in March, 31 days.
Highest follower count seen that year: 8,491.
January
Jan 1 01:00–10:00, 16:00–17:00, 19:00–20:00, 22:00–24:00 UTC Jan 2 00:00–09:00, 17:00–20:00, 23:00–24:00 UTC Jan 3 00:00–01:00, 04:00–07:00, 17:00–23:00 UTC Jan 4 03:00–09:00, 22:00–23:00 UTC Jan 5 03:00–06:00, 17:00–18:00, 21:00–24:00 UTC Jan 6 04:00–08:00, 22:00–23:00 UTC Jan 7 21:00–24:00 UTC Jan 8 00:00–01:00, 03:00–05:00, 17:00–24:00 UTC Jan 9 04:00–08:00, 17:00–19:00, 23:00–24:00 UTC Jan 10 03:00–07:00, 16:00–17:00, 21:00–22:00 UTC Jan 11 02:00–07:00, 10:00–12:00, 14:00–19:00 UTC Jan 12 00:00–08:00, 15:00–16:00, 22:00–24:00 UTC Jan 13 01:00–07:00, 17:00–24:00 UTC Jan 14 01:00–09:00 UTC Jan 15 03:00–07:00, 17:00–20:00 UTC Jan 16 04:00–06:00, 17:00–18:00, 22:00–24:00 UTC Jan 17 03:00–08:00 UTC Jan 18 03:00–06:00, 20:00–21:00 UTC Jan 19 17:00–18:00 UTC Jan 20 03:00–07:00, 17:00–20:00 UTC Jan 21 03:00–09:00, 17:00–19:00, 21:00–24:00 UTC Jan 22 03:00–09:00, 15:00–18:00, 20:00–23:00 UTC Jan 23 03:00–07:00, 16:00–19:00, 21:00–24:00 UTC Jan 24 05:00–08:00, 10:00–11:00, 18:00–22:00 UTC Jan 25 04:00–06:00, 17:00–18:00 UTC Jan 26 03:00–09:00, 11:00–13:00, 16:00–17:00 UTC Jan 27 03:00–06:00, 08:00–09:00, 15:00–17:00 UTC Jan 28 02:00–03:00, 07:00–09:00, 16:00–24:00 UTC Jan 29 00:00–01:00, 03:00–07:00, 16:00–18:00, 21:00–23:00 UTC Jan 30 05:00–06:00, 19:00–21:00, 23:00–24:00 UTC Jan 31 15:00–18:00, 21:00–24:00 UTC
February
Feb 1 04:00–08:00, 12:00–13:00 UTC Feb 2 09:00–11:00, 19:00–23:00 UTC Feb 3 03:00–06:00, 15:00–17:00, 20:00–24:00 UTC Feb 4 18:00–19:00 UTC Feb 5 03:00–06:00, 15:00–20:00 UTC Feb 6 03:00–05:00, 10:00–22:00 UTC Feb 7 18:00–20:00 UTC Feb 8 17:00–20:00 UTC Feb 9 03:00–07:00, 14:00–22:00 UTC Feb 10 03:00–04:00, 13:00–22:00 UTC Feb 11 03:00–05:00, 13:00–14:00, 17:00–22:00 UTC Feb 12 03:00–05:00, 13:00–22:00 UTC Feb 13 08:00–09:00, 19:00–24:00 UTC Feb 14 02:00–04:00, 06:00–08:00, 16:00–22:00 UTC Feb 15 04:00–06:00, 16:00–19:00 UTC Feb 16 13:00–15:00, 17:00–23:00 UTC Feb 17 04:00–08:00, 15:00–22:00 UTC Feb 18 03:00–05:00, 13:00–23:00 UTC Feb 19 13:00–24:00 UTC Feb 20 03:00–05:00, 08:00–09:00, 13:00–17:00, 20:00–22:00 UTC Feb 21 16:00–18:00, 23:00–24:00 UTC Feb 22 00:00–01:00, 04:00–07:00, 15:00–17:00 UTC Feb 23 04:00–05:00, 14:00–24:00 UTC Feb 24 04:00–06:00, 13:00–19:00, 21:00–24:00 UTC Feb 25 03:00–05:00, 08:00–11:00, 13:00–19:00 UTC Feb 26 03:00–08:00, 14:00–22:00 UTC Feb 27 03:00–10:00, 13:00–20:00 UTC Feb 28 04:00–06:00, 09:00–11:00, 17:00–18:00, 21:00–22:00 UTC
March
Mar 1 08:00–11:00, 15:00–24:00 UTC Mar 2 02:00–05:00, 09:00–11:00, 13:00–19:00, 21:00–22:00 UTC Mar 3 04:00–05:00, 07:00–10:00, 14:00–17:00, 19:00–20:00 UTC Mar 4 02:00–05:00, 08:00–09:00, 13:00–16:00, 21:00–22:00 UTC Mar 5 02:00–05:00, 09:00–10:00, 13:00–14:00, 16:00–20:00 UTC Mar 6 02:00–04:00, 16:00–19:00 UTC Mar 7 00:00–05:00, 16:00–17:00 UTC Mar 8 05:00–07:00, 12:00–19:00 UTC Mar 9 13:00–14:00, 16:00–23:00 UTC Mar 10 03:00–05:00, 07:00–09:00, 13:00–22:00 UTC Mar 11 02:00–05:00, 10:00–11:00, 13:00–22:00 UTC Mar 12 03:00–09:00, 13:00–18:00, 21:00–22:00 UTC Mar 13 09:00–10:00, 17:00–20:00, 22:00–24:00 UTC Mar 14 01:00–09:00, 16:00–18:00, 20:00–22:00 UTC Mar 15 05:00–11:00, 16:00–18:00 UTC Mar 16 01:00–05:00, 10:00–11:00, 14:00–15:00, 18:00–22:00 UTC Mar 17 02:00–04:00, 10:00–11:00, 13:00–22:00 UTC Mar 18 04:00–10:00, 13:00–18:00, 23:00–24:00 UTC Mar 19 04:00–09:00, 15:00–19:00, 21:00–22:00 UTC Mar 20 04:00–05:00, 08:00–11:00, 15:00–21:00 UTC Mar 21 03:00–07:00, 14:00–16:00 UTC Mar 22 05:00–08:00, 12:00–13:00, 15:00–16:00, 19:00–24:00 UTC Mar 23 03:00–08:00, 12:00–14:00 UTC Mar 24 02:00–05:00, 10:00–11:00, 14:00–17:00, 22:00–23:00 UTC Mar 25 03:00–09:00, 13:00–15:00, 17:00–22:00 UTC Mar 26 04:00–07:00, 13:00–18:00 UTC Mar 27 00:00–04:00, 06:00–11:00, 13:00–14:00, 18:00–20:00 UTC Mar 28 00:00–05:00, 07:00–12:00, 17:00–18:00 UTC Mar 29 04:00–06:00, 10:00–15:00, 23:00–24:00 UTC Mar 30 01:00–06:00, 20:00–22:00 UTC Mar 31 02:00–04:00, 10:00–12:00, 16:00–22:00 UTC
April
Apr 1 08:00–09:00, 17:00–18:00 UTC Apr 2 03:00–05:00, 09:00–11:00, 14:00–18:00 UTC Apr 3 02:00–04:00, 10:00–11:00, 16:00–17:00 UTC Apr 4 03:00–05:00, 09:00–13:00, 21:00–22:00 UTC Apr 5 04:00–05:00, 10:00–11:00, 15:00–18:00 UTC Apr 6 02:00–05:00, 07:00–09:00, 13:00–20:00 UTC Apr 8 04:00–05:00, 07:00–08:00, 14:00–16:00 UTC Apr 9 03:00–04:00, 06:00–08:00, 14:00–17:00 UTC Apr 10 06:00–07:00, 16:00–19:00 UTC Apr 11 05:00–06:00, 09:00–10:00, 16:00–19:00 UTC Apr 12 08:00–12:00, 16:00–17:00, 20:00–23:00 UTC Apr 13 03:00–06:00, 13:00–18:00 UTC Apr 14 14:00–17:00, 20:00–24:00 UTC Apr 15 02:00–04:00, 09:00–11:00, 13:00–24:00 UTC Apr 16 04:00–06:00, 14:00–20:00 UTC Apr 17 19:00–21:00, 23:00–24:00 UTC Apr 18 00:00–02:00, 05:00–07:00, 15:00–16:00, 18:00–22:00 UTC Apr 19 10:00–11:00, 13:00–14:00 UTC Apr 20 02:00–07:00, 14:00–22:00 UTC Apr 21 02:00–03:00, 06:00–10:00, 15:00–16:00, 18:00–21:00 UTC Apr 22 09:00–10:00, 14:00–21:00, 23:00–24:00 UTC Apr 23 00:00–01:00, 03:00–05:00, 10:00–11:00, 13:00–15:00, 18:00–24:00 UTC Apr 24 06:00–09:00, 14:00–24:00 UTC Apr 25 06:00–10:00, 16:00–20:00 UTC Apr 26 10:00–11:00 UTC Apr 27 04:00–06:00, 08:00–10:00, 14:00–21:00 UTC Apr 28 03:00–05:00, 07:00–11:00, 15:00–19:00 UTC Apr 29 03:00–05:00, 10:00–11:00, 18:00–22:00 UTC Apr 30 03:00–04:00, 09:00–10:00, 19:00–22:00 UTC
May
May 1 01:00–02:00, 06:00–09:00, 15:00–16:00, 20:00–22:00 UTC May 2 07:00–10:00 UTC May 3 02:00–06:00, 10:00–12:00, 16:00–18:00, 23:00–24:00 UTC May 4 01:00–02:00, 16:00–22:00 UTC May 5 09:00–11:00, 17:00–22:00 UTC May 6 08:00–10:00, 15:00–18:00, 20:00–22:00 UTC May 7 04:00–05:00, 09:00–11:00, 13:00–20:00 UTC May 8 07:00–09:00, 14:00–15:00, 18:00–24:00 UTC May 9 21:00–24:00 UTC May 10 04:00–06:00, 08:00–12:00, 15:00–16:00, 21:00–22:00 UTC May 11 08:00–09:00, 17:00–21:00 UTC May 12 04:00–07:00, 16:00–22:00 UTC May 13 08:00–09:00, 18:00–20:00 UTC May 14 04:00–06:00, 15:00–16:00, 19:00–20:00 UTC May 15 03:00–06:00, 14:00–17:00, 20:00–22:00 UTC May 16 01:00–02:00, 04:00–08:00, 10:00–11:00, 16:00–18:00, 22:00–23:00 UTC May 17 02:00–03:00, 09:00–11:00, 20:00–22:00 UTC May 18 00:00–10:00, 22:00–23:00 UTC May 19 17:00–22:00 UTC May 20 07:00–11:00, 14:00–22:00 UTC May 21 03:00–05:00, 16:00–20:00 UTC May 22 04:00–05:00, 10:00–11:00, 13:00–22:00 UTC May 23 03:00–05:00, 08:00–09:00, 16:00–17:00 UTC May 24 19:00–20:00 UTC May 25 05:00–06:00, 10:00–11:00, 15:00–19:00, 21:00–22:00 UTC May 26 03:00–06:00, 16:00–19:00, 21:00–23:00 UTC May 27 02:00–04:00, 14:00–23:00 UTC May 28 00:00–01:00, 04:00–05:00, 08:00–10:00, 13:00–16:00, 18:00–22:00 UTC May 29 02:00–07:00, 14:00–19:00 UTC May 30 03:00–07:00, 15:00–23:00 UTC May 31 15:00–17:00, 21:00–22:00 UTC
June
Jun 1 01:00–05:00, 07:00–08:00, 16:00–19:00 UTC Jun 2 08:00–09:00, 13:00–24:00 UTC Jun 3 06:00–07:00, 20:00–22:00 UTC Jun 4 07:00–08:00, 17:00–22:00 UTC Jun 5 04:00–06:00, 16:00–21:00 UTC Jun 6 04:00–05:00, 08:00–10:00, 12:00–13:00, 21:00–24:00 UTC Jun 7 04:00–07:00, 14:00–15:00, 22:00–23:00 UTC Jun 8 03:00–04:00, 14:00–17:00, 23:00–24:00 UTC Jun 9 03:00–04:00, 16:00–21:00 UTC Jun 10 03:00–06:00, 17:00–18:00 UTC Jun 11 08:00–09:00, 19:00–23:00 UTC Jun 12 00:00–04:00, 15:00–18:00, 20:00–22:00 UTC Jun 13 11:00–14:00, 18:00–19:00 UTC Jun 15 15:00–21:00 UTC Jun 16 05:00–07:00, 09:00–12:00 UTC Jun 17 04:00–07:00, 10:00–14:00 UTC Jun 22 16:00–21:00 UTC Jun 23 17:00–21:00 UTC Jun 24 03:00–05:00, 07:00–09:00, 18:00–20:00, 23:00–24:00 UTC Jun 25 06:00–08:00, 14:00–15:00, 17:00–18:00, 20:00–24:00 UTC Jun 26 08:00–09:00, 13:00–14:00, 18:00–20:00 UTC Jun 27 03:00–06:00, 16:00–18:00 UTC Jun 28 10:00–11:00, 20:00–24:00 UTC Jun 29 09:00–10:00, 17:00–24:00 UTC Jun 30 03:00–05:00, 22:00–23:00 UTC
July
Jul 1 03:00–05:00, 13:00–14:00, 20:00–24:00 UTC Jul 2 04:00–06:00, 11:00–12:00, 17:00–18:00 UTC Jul 3 04:00–05:00, 07:00–08:00 UTC Jul 4 04:00–06:00, 11:00–13:00 UTC Jul 5 03:00–07:00, 12:00–13:00, 22:00–24:00 UTC Jul 6 03:00–05:00, 15:00–16:00, 18:00–22:00 UTC Jul 7 05:00–06:00 UTC Jul 8 02:00–06:00, 17:00–20:00 UTC Jul 9 04:00–06:00, 11:00–12:00, 15:00–16:00, 18:00–19:00, 21:00–24:00 UTC Jul 10 03:00–07:00, 17:00–22:00 UTC Jul 11 11:00–12:00, 23:00–24:00 UTC Jul 12 01:00–06:00, 10:00–14:00 UTC Jul 13 03:00–04:00 UTC Jul 14 04:00–05:00, 10:00–11:00, 15:00–22:00 UTC Jul 15 00:00–01:00, 21:00–24:00 UTC Jul 16 04:00–08:00, 14:00–19:00, 21:00–23:00 UTC Jul 17 03:00–08:00, 10:00–11:00, 15:00–16:00, 20:00–23:00 UTC Jul 18 04:00–08:00, 16:00–17:00, 19:00–21:00 UTC Jul 19 02:00–10:00, 17:00–19:00 UTC Jul 20 04:00–07:00, 22:00–24:00 UTC Jul 21 00:00–01:00, 16:00–22:00 UTC Jul 22 00:00–01:00, 03:00–05:00, 11:00–12:00, 14:00–23:00 UTC Jul 23 17:00–24:00 UTC Jul 24 05:00–06:00, 09:00–12:00, 14:00–15:00, 19:00–20:00 UTC Jul 25 01:00–02:00, 17:00–23:00 UTC Jul 27 07:00–11:00, 14:00–15:00, 19:00–20:00 UTC