Most often in May, 31 days.
Highest follower count seen that year: 18,435.
January
Jan 1 00:00–05:00, 19:00–23:00 Jan 2 06:00–12:00, 20:00–23:00 Jan 3 08:00–11:00, 19:00–21:00, 23:00–24:00 Jan 4 07:00–12:00, 20:00–23:00 Jan 5 07:00–12:00 Jan 9 07:00–09:00, 20:00–23:00 Jan 10 07:00–11:00, 20:00–24:00 Jan 11 06:00–11:00 Jan 12 03:00–11:00, 20:00–24:00 Jan 13 00:00–02:00, 19:00–23:00 Jan 14 05:00–11:00, 20:00–24:00 Jan 15 00:00–01:00, 06:00–11:00, 20:00–24:00 Jan 16 00:00–01:00, 09:00–11:00, 20:00–22:00 Jan 17 07:00–11:00, 20:00–24:00 Jan 18 00:00–03:00, 08:00–12:00, 20:00–23:00 Jan 19 00:00–02:00, 08:00–11:00, 20:00–24:00 Jan 20 00:00–02:00, 08:00–11:00, 20:00–24:00 Jan 21 00:00–02:00, 09:00–11:00, 20:00–24:00 Jan 22 00:00–03:00, 09:00–10:00, 20:00–24:00 Jan 23 00:00–03:00, 07:00–10:00, 22:00–24:00 Jan 24 04:00–11:00, 20:00–23:00 Jan 25 05:00–10:00, 19:00–20:00, 22:00–23:00 Jan 26 08:00–11:00, 20:00–24:00 Jan 27 06:00–07:00, 09:00–10:00, 19:00–23:00 Jan 28 20:00–23:00 Jan 29 03:00–07:00, 10:00–11:00, 20:00–23:00 Jan 30 00:00–02:00, 19:00–24:00 Jan 31 05:00–07:00, 09:00–11:00, 19:00–24:00
February
Feb 1 03:00–05:00, 19:00–23:00 Feb 2 03:00–11:00, 20:00–21:00, 23:00–24:00 Feb 3 04:00–11:00, 19:00–21:00 Feb 4 00:00–04:00, 20:00–23:00 Feb 5 02:00–06:00, 10:00–11:00 Feb 6 20:00–22:00 Feb 7 05:00–11:00, 20:00–23:00 Feb 8 00:00–01:00, 08:00–11:00, 20:00–23:00 Feb 9 00:00–06:00, 08:00–11:00, 20:00–24:00 Feb 10 06:00–11:00, 20:00–24:00 Feb 11 00:00–03:00, 09:00–12:00, 20:00–24:00 Feb 12 00:00–02:00, 20:00–24:00 Feb 13 07:00–11:00, 19:00–23:00 Feb 14 07:00–11:00, 20:00–22:00 Feb 15 07:00–10:00, 19:00–24:00 Feb 16 20:00–24:00 Feb 17 00:00–02:00, 09:00–11:00, 20:00–22:00 Feb 18 19:00–24:00 Feb 19 03:00–11:00, 19:00–23:00 Feb 20 03:00–07:00, 19:00–24:00 Feb 21 05:00–11:00, 22:00–24:00 Feb 22 07:00–11:00, 20:00–23:00 Feb 23 02:00–07:00, 20:00–24:00 Feb 24 06:00–07:00, 09:00–12:00 Feb 26 20:00–24:00 Feb 27 09:00–11:00, 20:00–24:00 Feb 28 05:00–11:00, 20:00–24:00
March
Mar 1 00:00–04:00, 19:00–23:00 Mar 2 20:00–24:00 Mar 3 04:00–07:00, 09:00–11:00, 19:00–20:00 Mar 4 05:00–11:00 Mar 6 20:00–21:00 Mar 7 07:00–11:00, 20:00–23:00 Mar 8 22:00–24:00 Mar 9 00:00–01:00, 06:00–10:00, 22:00–23:00 Mar 10 07:00–12:00, 20:00–24:00 Mar 11 07:00–12:00, 20:00–24:00 Mar 12 06:00–11:00, 21:00–24:00 Mar 13 06:00–10:00, 19:00–23:00 Mar 14 03:00–11:00, 20:00–23:00 Mar 15 05:00–12:00, 20:00–21:00 Mar 16 04:00–11:00, 19:00–23:00 Mar 17 04:00–06:00, 08:00–11:00, 19:00–23:00 Mar 18 03:00–11:00, 20:00–24:00 Mar 19 04:00–12:00, 19:00–24:00 Mar 20 04:00–11:00, 20:00–23:00 Mar 21 03:00–11:00, 20:00–23:00 Mar 22 03:00–11:00, 19:00–23:00 Mar 23 03:00–11:00, 20:00–24:00 Mar 24 04:00–11:00, 19:00–23:00 Mar 25 04:00–11:00, 20:00–23:00 Mar 26 03:00–11:00, 20:00–23:00 Mar 27 03:00–11:00, 20:00–22:00 Mar 28 04:00–11:00 Mar 29 08:00–11:00, 20:00–24:00 Mar 30 00:00–01:00, 05:00–11:00, 20:00–22:00 Mar 31 06:00–11:00, 20:00–21:00
April
Apr 1 00:00–04:00, 23:00–24:00 Apr 2 06:00–11:00, 20:00–21:00, 23:00–24:00 Apr 3 00:00–03:00 Apr 4 01:00–02:00, 08:00–11:00, 20:00–23:00 Apr 5 08:00–11:00 Apr 9 02:00–06:00, 09:00–11:00 Apr 10 00:00–01:00, 20:00–21:00 Apr 11 06:00–08:00, 20:00–24:00 Apr 12 00:00–03:00, 07:00–11:00, 20:00–24:00 Apr 13 08:00–11:00, 21:00–22:00 Apr 14 19:00–24:00 Apr 15 04:00–06:00, 08:00–11:00, 20:00–23:00 Apr 16 06:00–11:00 Apr 17 00:00–07:00 Apr 18 01:00–11:00 Apr 19 06:00–11:00 Apr 20 00:00–10:00 Apr 21 00:00–03:00, 05:00–07:00, 09:00–10:00, 23:00–24:00 Apr 22 00:00–11:00, 23:00–24:00 Apr 23 00:00–04:00, 06:00–10:00 Apr 24 00:00–05:00, 07:00–11:00, 23:00–24:00 Apr 25 00:00–04:00 Apr 26 03:00–11:00 Apr 27 02:00–11:00 Apr 28 02:00–06:00 Apr 29 07:00–10:00, 20:00–24:00 Apr 30 07:00–11:00
May
May 1 20:00–24:00 May 2 06:00–11:00 May 3 21:00–24:00 May 4 00:00–01:00, 06:00–12:00 May 5 07:00–11:00, 20:00–21:00, 23:00–24:00 May 6 00:00–01:00, 08:00–11:00 May 7 02:00–11:00 May 8 05:00–11:00, 20:00–21:00, 23:00–24:00 May 9 05:00–12:00, 20:00–23:00 May 10 07:00–11:00, 19:00–22:00 May 11 20:00–21:00 May 12 08:00–12:00, 20:00–23:00 May 13 19:00–21:00 May 14 06:00–11:00, 19:00–24:00 May 15 08:00–11:00, 22:00–23:00 May 16 00:00–01:00, 08:00–12:00 May 17 05:00–07:00, 09:00–11:00, 19:00–23:00 May 18 07:00–11:00, 19:00–23:00 May 19 07:00–11:00, 20:00–22:00 May 20 11:00–13:00 May 21 10:00–13:00, 20:00–23:00 May 22 09:00–13:00, 21:00–24:00 May 23 00:00–01:00, 09:00–10:00, 21:00–23:00 May 24 00:00–02:00, 12:00–15:00, 21:00–24:00 May 25 10:00–13:00, 21:00–24:00 May 26 00:00–01:00, 08:00–13:00, 21:00–23:00 May 27 09:00–13:00, 21:00–23:00 May 28 10:00–12:00 May 29 08:00–11:00, 21:00–24:00 May 30 00:00–01:00, 11:00–14:00, 21:00–24:00 May 31 10:00–14:00
June
Jun 1 08:00–10:00, 21:00–24:00 Jun 2 21:00–24:00 Jun 3 10:00–13:00, 22:00–24:00 Jun 4 22:00–24:00 Jun 5 00:00–02:00, 11:00–14:00, 22:00–24:00 Jun 6 00:00–01:00, 10:00–13:00, 23:00–24:00 Jun 7 00:00–02:00, 23:00–24:00 Jun 8 00:00–02:00, 10:00–11:00, 21:00–23:00 Jun 9 08:00–10:00, 21:00–24:00 Jun 10 00:00–01:00, 10:00–11:00 Jun 11 07:00–11:00, 21:00–24:00 Jun 12 23:00–24:00 Jun 13 00:00–01:00 Jun 15 08:00–13:00 Jun 16 09:00–12:00, 21:00–24:00 Jun 17 23:00–24:00 Jun 18 00:00–03:00, 21:00–24:00 Jun 19 00:00–01:00 Jun 20 00:00–02:00, 22:00–24:00 Jun 21 00:00–03:00, 09:00–12:00, 21:00–24:00 Jun 25 00:00–01:00, 09:00–13:00, 21:00–24:00 Jun 26 00:00–02:00, 21:00–23:00 Jun 27 23:00–24:00 Jun 28 21:00–24:00 Jun 29 08:00–11:00, 20:00–24:00 Jun 30 00:00–01:00, 21:00–24:00
July
Jul 1 00:00–04:00, 21:00–24:00 Jul 2 20:00–24:00 Jul 3 10:00–13:00, 23:00–24:00 Jul 4 00:00–04:00, 21:00–24:00 Jul 5 01:00–05:00, 20:00–24:00 Jul 6 00:00–01:00, 08:00–11:00, 21:00–24:00 Jul 7 21:00–24:00 Jul 8 00:00–01:00, 21:00–24:00 Jul 9 00:00–01:00, 07:00–11:00, 21:00–24:00 Jul 10 00:00–01:00, 21:00–24:00 Jul 11 00:00–03:00, 21:00–24:00 Jul 12 00:00–02:00, 09:00–14:00, 21:00–24:00 Jul 13 00:00–01:00, 22:00–24:00 Jul 14 00:00–02:00, 22:00–24:00 Jul 15 00:00–02:00, 22:00–24:00 Jul 16 00:00–02:00, 07:00–08:00, 21:00–24:00 Jul 17 00:00–01:00, 08:00–11:00, 22:00–23:00 Jul 18 00:00–06:00, 22:00–24:00 Jul 19 01:00–06:00, 22:00–24:00 Jul 20 00:00–01:00, 06:00–08:00, 23:00–24:00 Jul 21 00:00–01:00, 21:00–24:00 Jul 22 00:00–01:00, 22:00–23:00 Jul 24 01:00–04:00, 10:00–13:00, 23:00–24:00 Jul 25 00:00–01:00, 22:00–24:00 Jul 26 00:00–02:00, 21:00–24:00 Jul 27 08:00–09:00