My pool profile expires in a month with no ITA — do I lose my CRS history if I resubmit?

A new profile is a fresh entry into the pool, it doesn't carry over your time-in-pool history, but your actual CRS SCORE is just recalculated fresh from your real facts (age, language, education, experience) at resubmission — so if nothing about your profile has changed, your score should be about the same (age-related points can tick down slightly each year, so double check that). Just make sure every section is re-entered accurately rather than copy-pasted blind.