Most often in March, 31 days.
Highest follower count seen that year: 995.
February
Feb 21 05:00–06:00, 10:00–14:00, 16:00–18:00, 21:00–22:00 Feb 22 22:00–23:00 Feb 23 02:00–03:00, 13:00–14:00, 16:00–19:00, 22:00–24:00 Feb 24 01:00–03:00, 14:00–18:00, 22:00–23:00 Feb 25 02:00–03:00, 12:00–16:00, 20:00–24:00 Feb 26 00:00–02:00, 08:00–11:00, 14:00–18:00, 20:00–21:00 Feb 27 00:00–01:00, 20:00–21:00 Feb 28 06:00–07:00, 13:00–15:00, 17:00–21:00
March
Mar 1 04:00–05:00, 18:00–20:00 Mar 2 02:00–04:00, 13:00–17:00 Mar 3 02:00–04:00, 10:00–19:00, 23:00–24:00 Mar 4 03:00–04:00, 15:00–16:00 Mar 5 08:00–09:00, 15:00–20:00 Mar 6 02:00–03:00, 17:00–19:00 Mar 7 01:00–04:00, 09:00–10:00, 16:00–20:00, 23:00–24:00 Mar 8 05:00–06:00, 14:00–21:00 Mar 9 00:00–01:00, 14:00–17:00 Mar 10 00:00–02:00, 13:00–16:00 Mar 11 02:00–03:00, 20:00–21:00 Mar 12 00:00–01:00, 12:00–15:00, 19:00–20:00 Mar 13 14:00–15:00, 17:00–18:00 Mar 14 01:00–03:00, 17:00–18:00, 20:00–21:00 Mar 15 03:00–04:00, 21:00–22:00 Mar 16 02:00–04:00, 11:00–15:00, 17:00–18:00, 20:00–23:00 Mar 17 03:00–07:00, 12:00–13:00, 15:00–16:00, 21:00–22:00 Mar 18 07:00–08:00, 14:00–15:00, 17:00–18:00 Mar 19 01:00–02:00, 11:00–12:00, 19:00–20:00 Mar 20 13:00–14:00 Mar 21 10:00–11:00, 16:00–18:00 Mar 22 04:00–05:00, 12:00–13:00, 15:00–20:00 Mar 23 01:00–02:00, 15:00–17:00, 21:00–23:00 Mar 24 17:00–19:00, 21:00–24:00 Mar 25 14:00–15:00, 17:00–19:00 Mar 26 04:00–05:00, 12:00–16:00, 21:00–24:00 Mar 27 03:00–04:00, 09:00–11:00, 15:00–16:00 Mar 28 14:00–15:00, 19:00–20:00 Mar 29 01:00–03:00, 16:00–17:00, 20:00–22:00 Mar 30 12:00–15:00, 20:00–23:00 Mar 31 03:00–04:00, 12:00–17:00
April
Apr 1 19:00–20:00 Apr 2 04:00–05:00, 16:00–19:00, 21:00–24:00 Apr 3 10:00–11:00 Apr 4 03:00–06:00, 14:00–15:00, 17:00–24:00 Apr 5 00:00–03:00, 10:00–11:00, 14:00–16:00, 18:00–19:00, 21:00–22:00 Apr 6 10:00–12:00, 15:00–16:00, 21:00–22:00 Apr 7 14:00–16:00, 20:00–21:00, 23:00–24:00 Apr 8 02:00–03:00 Apr 9 09:00–11:00, 13:00–14:00 Apr 10 02:00–03:00, 10:00–11:00, 16:00–17:00 Apr 11 08:00–09:00, 11:00–13:00, 21:00–22:00 Apr 12 16:00–17:00 Apr 13 01:00–02:00, 10:00–13:00, 15:00–16:00 Apr 14 10:00–13:00, 22:00–23:00 Apr 15 07:00–08:00, 12:00–13:00, 16:00–17:00 Apr 16 03:00–05:00, 11:00–12:00, 15:00–18:00, 20:00–22:00 Apr 17 20:00–22:00 Apr 18 02:00–03:00, 11:00–12:00, 15:00–16:00 Apr 19 01:00–02:00, 05:00–06:00, 16:00–17:00 Apr 21 11:00–12:00 Apr 25 09:00–10:00 Apr 26 02:00–03:00 Apr 28 02:00–03:00, 10:00–11:00, 19:00–20:00 Apr 29 16:00–17:00
May
May 1 02:00–04:00 May 3 17:00–18:00 May 5 04:00–06:00, 18:00–21:00 May 6 13:00–14:00, 23:00–24:00 May 7 04:00–05:00, 15:00–16:00, 18:00–20:00 May 8 12:00–15:00, 17:00–18:00, 21:00–22:00 May 9 06:00–07:00, 17:00–18:00, 20:00–21:00 May 10 00:00–01:00, 10:00–15:00, 20:00–22:00 May 11 02:00–03:00, 09:00–15:00, 19:00–20:00, 22:00–24:00 May 12 00:00–01:00, 04:00–05:00, 13:00–16:00, 18:00–19:00 May 13 00:00–02:00 May 16 04:00–06:00, 15:00–19:00, 22:00–24:00 May 17 11:00–15:00, 20:00–21:00 May 18 11:00–14:00, 19:00–20:00 May 19 13:00–15:00 May 20 03:00–06:00, 17:00–19:00 May 21 03:00–06:00, 17:00–18:00 May 22 03:00–04:00, 14:00–18:00, 22:00–23:00 May 23 00:00–04:00, 12:00–15:00, 22:00–23:00 May 24 03:00–04:00, 06:00–07:00, 11:00–12:00, 14:00–15:00, 18:00–19:00 May 25 06:00–07:00, 12:00–15:00, 18:00–19:00 May 26 08:00–10:00, 12:00–14:00, 17:00–18:00 May 29 04:00–05:00, 10:00–11:00 May 30 10:00–11:00 May 31 14:00–15:00
June
Jun 2 16:00–17:00, 20:00–21:00 Jun 3 03:00–04:00 Jun 4 10:00–11:00 Jun 5 06:00–07:00, 09:00–10:00, 18:00–19:00, 22:00–23:00 Jun 7 05:00–06:00, 16:00–17:00 Jun 8 04:00–05:00 Jun 9 12:00–13:00 Jun 10 22:00–24:00 Jun 11 04:00–05:00, 12:00–14:00, 16:00–17:00, 20:00–21:00 Jun 12 05:00–06:00, 16:00–17:00 Jun 13 05:00–06:00, 11:00–13:00 Jun 15 02:00–03:00, 11:00–13:00, 15:00–16:00 Jun 17 17:00–19:00 Jun 18 10:00–13:00, 22:00–23:00 Jun 19 04:00–05:00, 20:00–21:00 Jun 20 13:00–17:00, 22:00–23:00 Jun 21 11:00–13:00, 18:00–19:00 Jun 22 13:00–14:00, 17:00–18:00, 20:00–21:00 Jun 23 18:00–19:00 Jun 24 10:00–13:00 Jun 25 09:00–10:00, 12:00–14:00, 18:00–19:00 Jun 26 03:00–04:00, 11:00–12:00, 23:00–24:00 Jun 27 11:00–14:00 Jun 28 03:00–04:00, 11:00–12:00, 15:00–16:00, 22:00–23:00 Jun 29 04:00–05:00, 11:00–12:00 Jun 30 21:00–22:00
July
Jul 1 04:00–05:00, 12:00–13:00 Jul 2 11:00–13:00, 20:00–21:00 Jul 3 09:00–11:00 Jul 4 03:00–04:00, 10:00–12:00 Jul 5 10:00–11:00, 16:00–17:00 Jul 6 02:00–03:00, 10:00–11:00 Jul 8 11:00–13:00 Jul 9 04:00–05:00 Jul 10 10:00–11:00 Jul 11 19:00–20:00 Jul 13 10:00–11:00, 14:00–15:00, 19:00–20:00 Jul 14 12:00–13:00 Jul 16 04:00–05:00, 11:00–17:00 Jul 17 04:00–05:00, 13:00–17:00 Jul 18 06:00–11:00 Jul 19 03:00–05:00 Jul 20 03:00–06:00 Jul 21 05:00–06:00, 23:00–24:00 Jul 22 00:00–01:00, 03:00–05:00 Jul 23 13:00–15:00, 17:00–18:00 Jul 24 18:00–21:00 Jul 25 04:00–05:00, 11:00–12:00