The difference between setting an appointed time for lessons and setting an appointed time for qiyaam al-layl
Question

                We hope that you can advise us. Is setting an appointed time each week for giving religious lectures or holding study circles a form of reprehensible bid’ah (innovation), on the grounds that that seeking knowledge is a form of worship? The Messenger (peace and blessings of Allaah be upon him) did not set appointed times for this act of worship. Following on from that, if a group of brothers agree to meet in the mosque on a particular night each month to perform qiyaam al-layl, is that bid’ah? Please quote the evidence (daleel) (concerning that).
Praise be to Allah. 
          Shaykh Muhammad ibn Saalih ibn ‘Uthaymeen (may Allaah 
          have mercy on him) was asked this question, and he replied as follows: 
 
          Setting aside a regular day for giving lectures or holding 
          a study circle is not a reprehensible bid’ah. Rather it is permissible, 
          as it is permissible to set aside a day in schools and institutes to 
          study fiqh, tafseer, etc. Undoubtedly seeking Islamic knowledge is a 
          form of worship but setting aside a particular day for it is something 
          which is dictated by our circumstances. It is in our interests to set 
          aside a specific day for that so that people will not be put in a difficult 
          position. Seeking knowledge is not an act of worship which is linked 
          to a specific time, rather it is to be done at times which are convenient. 
          But if a special day is set aside and is regarded as being solely for 
          seeking knowledge, then this is bid’ah. 
 
          With regard to a group agreeing to meet on a specific 
          night for qiyaam al-layl, this is bid’ah, because it is not prescribed 
          for a group to perform qiyaam al-layl together. But if this is done 
          occasionally and unintentionally, as happened in the case of the Prophet 
          
          (peace and blessings of Allaah be upon him) and ‘Abd-Allaah (may Allaah 
          be pleased with him), this is OK.