Most often in March, 30 days.
Highest follower count seen that year: 3,919.
January
Jan 15 19:00–24:00 Jan 16 00:00–02:00, 19:00–24:00 Jan 17 00:00–06:00 Jan 19 18:00–24:00 Jan 20 00:00–01:00, 18:00–24:00 Jan 21 00:00–05:00, 19:00–24:00 Jan 22 00:00–04:00, 20:00–24:00 Jan 23 00:00–02:00, 18:00–24:00 Jan 24 00:00–03:00, 05:00–09:00, 20:00–24:00 Jan 25 00:00–05:00 Jan 26 18:00–24:00 Jan 27 00:00–02:00, 18:00–24:00 Jan 28 00:00–09:00, 19:00–24:00 Jan 29 00:00–03:00, 19:00–22:00 Jan 30 00:00–07:00, 20:00–24:00 Jan 31 00:00–03:00, 19:00–24:00
February
Feb 1 00:00–06:00, 19:00–24:00 Feb 2 01:00–05:00, 19:00–23:00 Feb 3 00:00–03:00, 19:00–23:00 Feb 4 00:00–05:00, 19:00–24:00 Feb 5 00:00–03:00, 19:00–23:00 Feb 6 00:00–02:00, 19:00–21:00 Feb 7 00:00–06:00, 20:00–24:00 Feb 8 00:00–05:00 Feb 9 19:00–23:00 Feb 10 01:00–06:00, 20:00–24:00 Feb 11 00:00–05:00, 19:00–24:00 Feb 12 00:00–03:00, 20:00–24:00 Feb 13 01:00–05:00, 19:00–22:00 Feb 14 00:00–08:00, 19:00–24:00 Feb 15 00:00–06:00, 19:00–23:00 Feb 16 01:00–03:00, 17:00–21:00 Feb 17 20:00–23:00 Feb 18 01:00–09:00, 20:00–24:00 Feb 19 00:00–04:00, 19:00–23:00 Feb 20 00:00–05:00, 19:00–23:00 Feb 21 01:00–04:00, 19:00–24:00 Feb 22 00:00–03:00, 18:00–23:00 Feb 23 00:00–02:00, 19:00–23:00 Feb 24 19:00–24:00 Feb 25 00:00–05:00, 19:00–24:00 Feb 26 00:00–06:00, 18:00–24:00 Feb 27 00:00–08:00, 19:00–24:00 Feb 28 01:00–03:00, 18:00–24:00
March
Mar 1 00:00–02:00, 19:00–22:00 Mar 2 19:00–23:00 Mar 3 00:00–05:00, 19:00–24:00 Mar 4 01:00–03:00, 19:00–22:00 Mar 5 19:00–23:00 Mar 6 01:00–04:00, 19:00–24:00 Mar 7 01:00–08:00, 19:00–24:00 Mar 8 01:00–09:00, 19:00–23:00 Mar 10 20:00–24:00 Mar 11 02:00–03:00, 19:00–24:00 Mar 12 01:00–04:00, 19:00–24:00 Mar 13 00:00–03:00, 20:00–24:00 Mar 14 00:00–02:00, 20:00–24:00 Mar 15 00:00–02:00, 19:00–24:00 Mar 16 00:00–02:00, 19:00–23:00 Mar 17 00:00–03:00, 19:00–24:00 Mar 18 01:00–03:00, 19:00–24:00 Mar 19 00:00–04:00, 19:00–24:00 Mar 20 01:00–02:00, 04:00–05:00, 21:00–24:00 Mar 21 00:00–04:00, 20:00–24:00 Mar 22 00:00–06:00 Mar 23 18:00–24:00 Mar 24 00:00–07:00, 20:00–23:00 Mar 25 01:00–04:00 Mar 26 20:00–24:00 Mar 27 00:00–01:00, 03:00–06:00, 19:00–24:00 Mar 28 00:00–02:00, 04:00–05:00, 22:00–24:00 Mar 29 00:00–02:00, 04:00–08:00, 14:00–17:00 Mar 30 19:00–24:00 Mar 31 00:00–02:00, 19:00–24:00
April
Apr 1 00:00–04:00, 20:00–23:00 Apr 2 00:00–02:00, 19:00–24:00 Apr 3 02:00–07:00 Apr 4 03:00–05:00, 19:00–24:00 Apr 5 00:00–07:00 Apr 6 19:00–24:00 Apr 7 03:00–04:00, 20:00–24:00 Apr 8 02:00–06:00, 19:00–23:00 Apr 9 00:00–02:00, 22:00–24:00 Apr 10 00:00–01:00, 03:00–06:00, 20:00–21:00 Apr 12 19:00–24:00 Apr 13 01:00–03:00, 20:00–23:00 Apr 14 01:00–02:00, 20:00–24:00 Apr 15 02:00–07:00, 19:00–23:00 Apr 16 02:00–04:00, 20:00–24:00 Apr 17 02:00–04:00, 21:00–24:00 Apr 18 00:00–02:00, 20:00–24:00 Apr 19 00:00–01:00 Apr 20 19:00–23:00 Apr 21 18:00–24:00 Apr 22 03:00–05:00, 19:00–24:00 Apr 23 02:00–05:00, 21:00–24:00 Apr 24 20:00–24:00 Apr 25 00:00–02:00, 19:00–24:00 Apr 26 00:00–03:00, 20:00–22:00 Apr 27 00:00–02:00 Apr 28 20:00–24:00 Apr 29 00:00–03:00, 19:00–24:00 Apr 30 02:00–05:00, 20:00–23:00
May
May 1 00:00–02:00, 13:00–20:00 May 2 19:00–22:00 May 3 00:00–05:00 May 4 19:00–22:00 May 5 01:00–02:00, 19:00–24:00 May 6 00:00–05:00, 20:00–24:00 May 7 00:00–01:00, 03:00–04:00 May 8 19:00–23:00 May 9 19:00–24:00 May 10 00:00–02:00, 17:00–24:00 May 11 00:00–03:00, 19:00–23:00 May 12 19:00–23:00 May 13 01:00–03:00, 19:00–23:00 May 14 00:00–01:00, 03:00–05:00, 20:00–24:00 May 15 00:00–02:00, 19:00–23:00 May 16 01:00–02:00, 22:00–24:00 May 17 00:00–03:00 May 18 19:00–24:00 May 19 19:00–24:00 May 20 00:00–02:00, 17:00–22:00 May 21 01:00–03:00, 20:00–21:00, 23:00–24:00 May 22 00:00–03:00, 15:00–22:00 May 23 21:00–24:00 May 24 00:00–03:00, 17:00–24:00 May 26 19:00–24:00 May 27 00:00–02:00, 22:00–24:00 May 28 01:00–05:00, 19:00–23:00 May 29 00:00–03:00, 19:00–24:00 May 30 01:00–11:00, 19:00–23:00 May 31 00:00–03:00
June
Jun 1 19:00–23:00 Jun 2 01:00–03:00, 19:00–23:00 Jun 3 00:00–02:00, 19:00–24:00 Jun 4 21:00–24:00 Jun 5 01:00–05:00, 19:00–24:00 Jun 6 00:00–05:00 Jun 7 21:00–24:00 Jun 8 00:00–03:00, 05:00–10:00, 20:00–24:00 Jun 9 00:00–02:00, 19:00–24:00 Jun 10 01:00–03:00, 20:00–24:00 Jun 11 00:00–03:00, 20:00–24:00 Jun 12 00:00–03:00, 20:00–24:00 Jun 13 00:00–02:00 Jun 15 19:00–24:00 Jun 16 00:00–04:00, 19:00–24:00 Jun 17 02:00–04:00, 19:00–24:00 Jun 18 00:00–01:00, 19:00–24:00 Jun 19 00:00–03:00, 20:00–23:00 Jun 20 00:00–02:00, 19:00–23:00 Jun 21 00:00–07:00, 12:00–15:00 Jun 22 19:00–24:00 Jun 23 00:00–01:00 Jun 24 04:00–05:00, 19:00–21:00 Jun 25 00:00–02:00, 20:00–24:00 Jun 26 20:00–22:00 Jun 27 21:00–23:00 Jun 28 02:00–04:00 Jun 29 19:00–24:00 Jun 30 00:00–01:00, 13:00–17:00
July
Jul 1 03:00–05:00, 21:00–24:00 Jul 2 19:00–24:00 Jul 3 00:00–02:00, 19:00–24:00 Jul 4 00:00–02:00, 19:00–24:00 Jul 5 00:00–03:00, 05:00–10:00 Jul 6 21:00–24:00 Jul 7 00:00–02:00, 20:00–24:00 Jul 8 00:00–02:00 Jul 9 19:00–24:00 Jul 10 01:00–02:00, 18:00–24:00 Jul 11 00:00–01:00, 03:00–05:00, 19:00–24:00 Jul 12 00:00–01:00, 17:00–23:00 Jul 13 08:00–15:00 Jul 14 20:00–24:00 Jul 15 01:00–03:00, 20:00–24:00 Jul 16 01:00–04:00 Jul 17 21:00–24:00 Jul 18 00:00–02:00, 05:00–09:00 Jul 19 00:00–07:00