Most often in July, 25 days.
Highest follower count seen that year: 8,460.
January
Jan 3 14:00–24:00 Jan 4 00:00–02:00, 16:00–22:00 Jan 5 03:00–07:00 Jan 10 17:00–22:00 Jan 11 03:00–07:00, 16:00–21:00 Jan 12 12:00–16:00 Jan 15 11:00–19:00 Jan 16 17:00–21:00 Jan 25 03:00–09:00 Jan 27 06:00–12:00 Jan 28 04:00–08:00, 11:00–18:00 Jan 29 05:00–08:00, 12:00–17:00 Jan 30 06:00–09:00, 12:00–19:00 Jan 31 04:00–06:00, 11:00–13:00
February
Feb 7 22:00–24:00 Feb 8 00:00–02:00 Feb 9 00:00–07:00, 13:00–17:00 Feb 10 00:00–03:00 Feb 11 03:00–10:00 Feb 12 03:00–09:00 Feb 14 12:00–13:00 Feb 15 01:00–07:00, 11:00–15:00 Feb 16 02:00–10:00, 15:00–19:00 Feb 17 05:00–10:00, 19:00–23:00 Feb 18 08:00–10:00, 13:00–15:00, 18:00–20:00 Feb 26 01:00–08:00, 14:00–20:00
March
Mar 5 02:00–11:00 Mar 8 07:00–09:00 Mar 9 05:00–08:00, 12:00–15:00 Mar 10 04:00–07:00 Mar 11 04:00–09:00 Mar 13 04:00–09:00, 12:00–13:00 Mar 14 05:00–10:00 Mar 15 04:00–09:00 Mar 16 04:00–10:00 Mar 17 03:00–08:00 Mar 18 05:00–10:00 Mar 19 04:00–10:00 Mar 20 05:00–09:00 Mar 21 05:00–09:00 Mar 22 05:00–10:00 Mar 23 05:00–11:00 Mar 24 04:00–10:00 Mar 25 05:00–09:00, 13:00–17:00 Mar 26 04:00–09:00, 13:00–17:00 Mar 27 05:00–08:00 Mar 29 06:00–09:00 Mar 30 05:00–10:00, 14:00–17:00 Mar 31 07:00–08:00, 15:00–18:00
April
Apr 1 15:00–20:00 Apr 2 06:00–11:00, 13:00–16:00 Apr 3 05:00–10:00, 14:00–17:00 Apr 4 05:00–09:00 Apr 5 09:00–11:00, 13:00–16:00 Apr 6 06:00–09:00 Apr 8 06:00–10:00, 16:00–19:00 Apr 9 06:00–09:00, 12:00–15:00 Apr 11 05:00–09:00 Apr 12 06:00–09:00 Apr 13 05:00–13:00 Apr 14 06:00–08:00 Apr 16 02:00–09:00, 12:00–15:00 Apr 17 05:00–06:00 Apr 18 04:00–11:00 Apr 19 05:00–10:00, 13:00–16:00 Apr 20 05:00–10:00, 13:00–16:00 Apr 21 04:00–08:00, 12:00–13:00 Apr 22 05:00–09:00, 12:00–16:00 Apr 23 07:00–08:00 Apr 24 06:00–09:00 Apr 25 05:00–10:00 Apr 27 05:00–10:00 Apr 28 05:00–08:00 Apr 30 05:00–09:00
May
May 1 07:00–09:00, 22:00–24:00 May 2 00:00–03:00 May 3 05:00–11:00, 14:00–16:00 May 11 06:00–09:00 May 12 04:00–07:00, 11:00–16:00 May 13 06:00–09:00, 14:00–19:00 May 14 07:00–11:00 May 18 05:00–11:00, 15:00–19:00 May 19 11:00–19:00 May 20 05:00–09:00, 15:00–18:00 May 21 16:00–22:00 May 22 08:00–12:00, 16:00–21:00 May 23 08:00–12:00 May 24 16:00–22:00 May 25 06:00–11:00 May 26 14:00–19:00 May 27 08:00–11:00, 16:00–23:00 May 28 18:00–23:00 May 29 05:00–10:00 May 31 19:00–21:00
June
Jun 1 14:00–18:00 Jun 2 00:00–05:00 Jun 4 19:00–24:00 Jun 5 00:00–01:00, 20:00–24:00 Jun 6 00:00–02:00, 06:00–08:00 Jun 8 17:00–22:00 Jun 9 05:00–10:00, 18:00–23:00 Jun 11 19:00–23:00 Jun 12 05:00–10:00 Jun 16 18:00–24:00 Jun 17 05:00–08:00, 20:00–23:00 Jun 18 06:00–10:00, 18:00–24:00 Jun 19 05:00–07:00, 21:00–24:00 Jun 20 00:00–01:00, 07:00–09:00, 22:00–24:00 Jun 21 00:00–03:00 Jun 25 10:00–13:00, 17:00–22:00 Jun 26 18:00–23:00 Jun 27 00:00–01:00, 06:00–09:00, 11:00–12:00 Jun 28 04:00–08:00, 17:00–21:00 Jun 29 03:00–07:00 Jun 30 20:00–24:00
July
Jul 1 00:00–01:00, 06:00–10:00 Jul 2 16:00–22:00 Jul 3 03:00–05:00, 17:00–22:00 Jul 4 02:00–05:00 Jul 5 03:00–08:00, 11:00–15:00 Jul 6 04:00–10:00, 14:00–15:00, 18:00–19:00 Jul 8 01:00–07:00, 19:00–24:00 Jul 9 04:00–08:00, 10:00–11:00 Jul 10 04:00–08:00, 12:00–16:00 Jul 11 03:00–10:00 Jul 12 00:00–05:00 Jul 13 04:00–05:00, 09:00–15:00 Jul 14 03:00–09:00, 13:00–16:00 Jul 16 04:00–10:00 Jul 17 06:00–10:00, 16:00–20:00 Jul 18 06:00–10:00 Jul 19 02:00–09:00 Jul 20 06:00–13:00 Jul 21 06:00–07:00, 15:00–20:00 Jul 22 18:00–21:00 Jul 23 02:00–05:00, 07:00–09:00, 23:00–24:00 Jul 24 00:00–01:00, 19:00–23:00 Jul 25 18:00–21:00 Jul 26 04:00–06:00 Jul 27 06:00–10:00, 14:00–15:00