is the date by which comments must be returned (in writing) to the planning office. As far as I can see from the letter, it says they are asking for "comments and/or observations" (rather than objections). As the last planning meeting was on the 5th of January (http://www.eastcambs.gov.uk/docs/agendas/planning/pl050105ag.pdf), I assume the next meeting is probably going to follow rapidly after the 4th of February.
Feb 4th
As the last planning meeting was on the 5th of January (http://www.eastcambs.gov.uk/docs/agendas/planning/pl050105ag.pdf), I assume the next meeting is probably going to follow rapidly after the 4th of February.