Just wondering when you change your string????......Do you go by time, or number of shots????............My Savannah is about a year and a half old…..but the string only has approximately 1,000 shots on it…..had a 7 month lay off last year….the serving came loose and I had to put new serving on it, the string is not showing any sign of wear…….it’s stretched in and is not moving any more…….I’ve ordered a new string but haven’t put it on yet….Should I go ahead and change it or wait till I’ve got more shots or it starts to show sighs of wear…..don’t want it to break while at full draw….