Most often in April, 25 days.
Highest follower count seen that year: 7,380.
January
Jan 5 21:00–23:00 Jan 6 12:00–20:00 Jan 7 11:00–15:00, 18:00–21:00 Jan 8 05:00–09:00, 14:00–17:00, 21:00–23:00 Jan 9 15:00–22:00 Jan 10 15:00–20:00 Jan 11 12:00–21:00 Jan 12 12:00–15:00, 19:00–23:00 Jan 14 13:00–18:00 Jan 15 08:00–11:00 Jan 22 14:00–17:00, 19:00–23:00 Jan 23 14:00–15:00, 19:00–24:00 Jan 24 13:00–20:00 Jan 25 04:00–09:00, 14:00–18:00 Jan 26 08:00–13:00, 15:00–24:00 Jan 27 19:00–24:00 Jan 28 12:00–16:00, 18:00–20:00 Jan 29 02:00–07:00, 19:00–23:00 Jan 30 17:00–18:00, 23:00–24:00 Jan 31 02:00–07:00, 17:00–23:00
February
Feb 1 14:00–23:00 Feb 2 19:00–20:00, 22:00–23:00 Feb 3 11:00–12:00 Feb 4 13:00–20:00 Feb 5 11:00–13:00, 15:00–23:00 Feb 6 15:00–19:00 Feb 7 01:00–02:00, 14:00–23:00 Feb 8 05:00–09:00, 13:00–15:00, 17:00–19:00 Feb 10 12:00–23:00 Feb 11 12:00–15:00, 17:00–18:00, 22:00–23:00 Feb 12 12:00–16:00, 21:00–24:00 Feb 13 10:00–15:00, 18:00–24:00 Feb 14 00:00–02:00, 12:00–17:00 Feb 15 11:00–17:00, 21:00–23:00 Feb 16 16:00–20:00 Feb 17 13:00–22:00 Feb 18 12:00–13:00, 17:00–20:00 Feb 19 06:00–07:00, 09:00–18:00, 23:00–24:00 Feb 20 13:00–16:00 Feb 23 13:00–23:00 Feb 24 08:00–13:00, 19:00–21:00 Feb 26 12:00–20:00 Feb 28 12:00–13:00, 15:00–23:00
March
Mar 1 00:00–01:00, 12:00–13:00, 15:00–17:00, 19:00–24:00 Mar 2 13:00–17:00, 20:00–24:00 Mar 3 00:00–01:00, 13:00–14:00, 22:00–23:00 Mar 5 13:00–21:00 Mar 7 12:00–22:00 Mar 8 11:00–15:00, 22:00–24:00 Mar 9 09:00–13:00, 15:00–20:00, 22:00–23:00 Mar 10 06:00–13:00, 20:00–24:00 Mar 11 14:00–17:00 Mar 12 00:00–01:00, 13:00–19:00 Mar 13 11:00–14:00, 17:00–19:00 Mar 14 00:00–01:00, 11:00–14:00 Mar 15 12:00–13:00 Mar 16 04:00–07:00, 10:00–16:00, 18:00–19:00, 22:00–23:00 Mar 17 10:00–14:00, 22:00–23:00 Mar 18 11:00–13:00, 16:00–18:00 Mar 23 05:00–13:00
April
Apr 2 20:00–24:00 Apr 3 10:00–12:00 Apr 4 11:00–24:00 Apr 5 10:00–23:00 Apr 7 10:00–18:00, 20:00–21:00 Apr 8 06:00–09:00, 20:00–21:00 Apr 9 08:00–13:00, 16:00–17:00 Apr 10 16:00–21:00 Apr 11 07:00–15:00, 17:00–20:00 Apr 12 06:00–22:00 Apr 13 02:00–05:00, 11:00–19:00, 21:00–22:00 Apr 14 12:00–19:00 Apr 15 15:00–19:00, 21:00–22:00 Apr 16 03:00–07:00, 12:00–23:00 Apr 17 14:00–15:00 Apr 18 16:00–17:00, 20:00–24:00 Apr 19 00:00–01:00, 07:00–15:00, 19:00–23:00 Apr 20 14:00–22:00 Apr 22 10:00–11:00, 16:00–19:00, 22:00–24:00 Apr 24 15:00–16:00, 18:00–24:00 Apr 25 00:00–01:00, 18:00–24:00 Apr 26 00:00–01:00, 08:00–17:00, 21:00–23:00 Apr 27 03:00–06:00, 16:00–18:00, 20:00–23:00 Apr 29 02:00–07:00, 14:00–23:00 Apr 30 09:00–19:00, 22:00–24:00
May
May 1 00:00–02:00, 17:00–21:00 May 2 05:00–06:00 May 3 18:00–23:00 May 4 07:00–09:00 May 5 04:00–12:00, 20:00–22:00 May 6 19:00–21:00 May 7 03:00–07:00, 13:00–14:00, 20:00–21:00 May 8 19:00–23:00 May 9 19:00–20:00 May 10 14:00–15:00 May 15 22:00–23:00 May 17 10:00–16:00, 20:00–24:00 May 18 13:00–14:00, 19:00–24:00 May 19 00:00–01:00, 13:00–15:00, 17:00–24:00 May 20 17:00–18:00 May 21 16:00–20:00 May 22 06:00–09:00, 19:00–20:00 May 23 02:00–03:00, 22:00–24:00 May 24 00:00–02:00, 12:00–19:00, 22:00–23:00 May 25 03:00–04:00, 11:00–14:00, 18:00–21:00 May 26 06:00–10:00, 23:00–24:00 May 27 17:00–20:00 May 28 02:00–05:00, 17:00–19:00, 22:00–24:00 May 29 00:00–01:00, 11:00–12:00, 17:00–20:00 May 30 15:00–17:00, 21:00–24:00
June
Jun 2 11:00–13:00, 17:00–22:00 Jun 3 23:00–24:00 Jun 4 22:00–23:00 Jun 5 13:00–15:00, 17:00–19:00 Jun 6 00:00–03:00, 17:00–22:00 Jun 7 10:00–17:00, 20:00–24:00 Jun 8 00:00–01:00, 20:00–21:00, 23:00–24:00 Jun 9 00:00–02:00 Jun 10 05:00–08:00, 21:00–22:00 Jun 11 01:00–02:00, 15:00–17:00 Jun 12 17:00–19:00, 23:00–24:00 Jun 13 16:00–19:00 Jun 16 01:00–05:00, 13:00–14:00 Jun 17 17:00–19:00, 21:00–24:00 Jun 18 15:00–19:00, 21:00–24:00 Jun 19 00:00–01:00, 11:00–17:00, 22:00–23:00 Jun 20 00:00–01:00, 14:00–17:00, 21:00–24:00 Jun 21 00:00–01:00, 17:00–22:00 Jun 22 00:00–01:00 Jun 23 00:00–01:00 Jun 30 03:00–04:00, 15:00–16:00
July
Jul 1 13:00–15:00, 17:00–19:00 Jul 2 19:00–23:00 Jul 3 13:00–14:00, 17:00–19:00, 21:00–24:00 Jul 4 17:00–24:00 Jul 5 00:00–01:00, 09:00–11:00, 23:00–24:00 Jul 6 00:00–01:00, 13:00–14:00, 18:00–22:00 Jul 7 21:00–23:00 Jul 8 21:00–24:00 Jul 9 01:00–04:00, 19:00–23:00 Jul 10 08:00–12:00, 14:00–17:00 Jul 14 01:00–05:00, 20:00–22:00 Jul 15 12:00–20:00 Jul 16 01:00–04:00, 13:00–14:00, 16:00–18:00, 20:00–23:00 Jul 17 04:00–12:00, 20:00–23:00 Jul 18 00:00–04:00 Jul 19 17:00–24:00 Jul 20 00:00–01:00, 15:00–17:00