Most often in January, 30 days.
Highest follower count seen that year: 2,474.
January
Jan 1 13:00–24:00 Jan 2 05:00–21:00 Jan 3 03:00–19:00 Jan 4 00:00–02:00, 17:00–21:00, 23:00–24:00 Jan 5 00:00–01:00, 04:00–12:00, 17:00–21:00 Jan 6 03:00–09:00, 13:00–18:00, 23:00–24:00 Jan 7 00:00–08:00, 11:00–19:00, 22:00–24:00 Jan 8 00:00–08:00, 10:00–14:00, 16:00–19:00, 23:00–24:00 Jan 9 00:00–03:00, 05:00–10:00, 16:00–17:00, 22:00–24:00 Jan 10 00:00–02:00, 04:00–09:00, 16:00–19:00, 23:00–24:00 Jan 11 00:00–02:00, 05:00–10:00, 12:00–22:00 Jan 12 03:00–06:00, 14:00–20:00 Jan 13 03:00–08:00, 12:00–20:00, 23:00–24:00 Jan 14 02:00–10:00, 14:00–19:00, 23:00–24:00 Jan 15 00:00–02:00, 04:00–07:00, 10:00–13:00, 16:00–20:00, 23:00–24:00 Jan 16 00:00–09:00, 14:00–21:00 Jan 17 01:00–05:00, 07:00–21:00 Jan 18 07:00–08:00, 13:00–19:00 Jan 19 00:00–08:00, 11:00–18:00, 23:00–24:00 Jan 20 00:00–01:00, 03:00–10:00, 12:00–20:00, 23:00–24:00 Jan 21 00:00–09:00, 14:00–22:00 Jan 22 00:00–09:00, 11:00–21:00 Jan 23 02:00–10:00, 12:00–19:00, 23:00–24:00 Jan 24 00:00–01:00, 05:00–10:00, 13:00–16:00 Jan 26 10:00–20:00, 23:00–24:00 Jan 27 00:00–01:00, 03:00–10:00, 12:00–20:00 Jan 28 00:00–21:00 Jan 29 00:00–08:00, 12:00–22:00 Jan 30 02:00–21:00 Jan 31 02:00–19:00
February
Feb 1 03:00–04:00, 07:00–09:00, 11:00–20:00 Feb 2 00:00–10:00, 12:00–20:00 Feb 3 00:00–09:00, 11:00–20:00 Feb 4 02:00–04:00, 10:00–19:00 Feb 5 02:00–05:00, 10:00–21:00 Feb 6 01:00–20:00 Feb 7 01:00–22:00 Feb 8 02:00–04:00, 08:00–20:00 Feb 9 02:00–09:00, 11:00–20:00 Feb 10 00:00–18:00 Feb 11 04:00–07:00, 10:00–17:00, 23:00–24:00 Feb 12 02:00–20:00 Feb 13 02:00–21:00 Feb 14 02:00–20:00 Feb 15 02:00–04:00, 07:00–09:00, 12:00–20:00 Feb 16 02:00–20:00 Feb 17 03:00–10:00 Feb 18 02:00–03:00, 07:00–08:00, 12:00–20:00 Feb 19 02:00–06:00, 08:00–20:00 Feb 20 03:00–09:00, 12:00–15:00, 17:00–19:00 Feb 21 02:00–04:00, 08:00–10:00, 12:00–13:00 Feb 22 14:00–16:00 Feb 23 02:00–10:00, 12:00–20:00 Feb 24 02:00–08:00, 11:00–22:00 Feb 25 02:00–21:00 Feb 26 01:00–23:00 Feb 27 03:00–09:00, 11:00–22:00 Feb 28 03:00–19:00
March
Mar 1 03:00–05:00, 10:00–19:00 Mar 2 00:00–21:00 Mar 3 03:00–05:00, 07:00–21:00 Mar 4 02:00–08:00, 13:00–22:00 Mar 5 02:00–18:00 Mar 6 03:00–04:00, 08:00–15:00, 17:00–21:00 Mar 7 01:00–10:00, 12:00–21:00 Mar 8 02:00–04:00, 07:00–20:00 Mar 9 02:00–03:00, 05:00–10:00, 12:00–20:00 Mar 10 02:00–21:00 Mar 11 02:00–21:00 Mar 12 02:00–20:00 Mar 13 03:00–14:00, 16:00–21:00 Mar 14 02:00–08:00, 12:00–22:00 Mar 15 03:00–04:00, 07:00–09:00, 12:00–19:00 Mar 16 01:00–19:00 Mar 17 02:00–15:00 Mar 20 07:00–14:00, 16:00–19:00, 23:00–24:00 Mar 21 00:00–09:00, 12:00–19:00 Mar 22 02:00–03:00, 07:00–18:00 Mar 23 01:00–21:00 Mar 24 02:00–03:00, 05:00–06:00, 08:00–09:00, 12:00–20:00 Mar 25 02:00–16:00, 18:00–20:00 Mar 26 02:00–05:00, 07:00–08:00, 10:00–20:00 Mar 27 02:00–20:00 Mar 28 02:00–06:00, 09:00–18:00 Mar 29 10:00–11:00, 15:00–18:00 Mar 30 06:00–17:00 Mar 31 02:00–03:00, 05:00–15:00
April
Apr 1 08:00–14:00, 16:00–19:00 Apr 2 02:00–06:00, 08:00–17:00, 22:00–24:00 Apr 3 03:00–11:00, 13:00–15:00 Apr 4 02:00–06:00, 10:00–18:00 Apr 5 03:00–05:00, 07:00–08:00, 10:00–18:00 Apr 6 00:00–01:00, 03:00–07:00, 13:00–19:00 Apr 7 02:00–06:00, 12:00–18:00 Apr 8 01:00–10:00, 13:00–18:00 Apr 9 00:00–01:00, 03:00–17:00 Apr 10 02:00–10:00, 13:00–19:00 Apr 11 04:00–09:00, 12:00–20:00 Apr 12 02:00–09:00, 13:00–17:00 Apr 13 02:00–19:00 Apr 14 03:00–07:00, 11:00–18:00 Apr 15 01:00–03:00, 05:00–06:00, 08:00–19:00 Apr 16 01:00–19:00, 23:00–24:00 Apr 17 00:00–01:00, 05:00–06:00, 10:00–13:00, 15:00–20:00 Apr 18 02:00–08:00, 10:00–18:00 Apr 19 05:00–19:00 Apr 20 02:00–18:00 Apr 21 02:00–11:00, 14:00–15:00, 17:00–19:00 Apr 22 02:00–19:00 Apr 23 01:00–14:00, 16:00–20:00 Apr 24 06:00–17:00 Apr 25 03:00–14:00, 16:00–18:00 Apr 26 01:00–02:00, 04:00–11:00, 14:00–18:00 Apr 27 02:00–08:00, 10:00–18:00 Apr 28 02:00–03:00, 05:00–19:00 Apr 29 04:00–18:00 Apr 30 03:00–11:00, 13:00–19:00
May
May 1 02:00–04:00, 06:00–08:00, 12:00–18:00, 22:00–24:00 May 2 00:00–01:00, 03:00–07:00 May 3 07:00–09:00, 11:00–12:00, 14:00–18:00, 23:00–24:00 May 4 05:00–09:00, 11:00–17:00 May 5 02:00–08:00, 10:00–20:00 May 6 02:00–03:00, 05:00–12:00, 14:00–17:00, 23:00–24:00 May 7 00:00–01:00, 04:00–17:00 May 8 09:00–14:00, 17:00–19:00 May 9 05:00–19:00 May 10 03:00–09:00, 11:00–18:00 May 11 02:00–07:00, 09:00–19:00 May 12 03:00–07:00, 11:00–19:00 May 13 03:00–09:00, 12:00–14:00, 16:00–18:00 May 14 05:00–17:00 May 15 03:00–15:00, 17:00–18:00
July
Jul 17 14:00–19:00 Jul 18 06:00–17:00 Jul 19 02:00–09:00, 11:00–20:00 Jul 20 03:00–09:00, 11:00–13:00