Is it permissible to consistently recite "Subhan Allah wa bihamdih" (Glory be to Allah and praise be to Him) 100 times before sleeping?

Regularly reciting "Subhanallahi wa bihamdihi" (Glory be to Allah and with His praise) one hundred times brings immense goodness and great reward. It is among the best forms of remembrance (dhikr), and through it, sins are effaced, even if they are like the foam of the sea, as reported by Abu Hurairah. It has been authentically narrated from the Prophet, peace and blessings be upon him, that reciting it one hundred times in the morning and in the evening leads to the forgiveness of sins. However, it is feared that consistently performing the dhikr "Subhanallahi wa bihamdihi" specifically before sleep, with the belief that it is sunnah at this time, might be an additive innovation (bid‘ah idafiyyah). This is because the Lawgiver (Shar'i) did not specify it among the remembrances for sleep. Therefore, it is advisable to change the time of this dhikr from time to time and not to restrict it specifically to before sleep.