Memory Maker Question for 2018

Hi, question is regarding MM our trip is on January 2018 and the last time I did a share was in 2016 and 2015 those times we had the whole 30 day photo ops and didnt DL til the 15th day Which then added 30 more days for photos at parks taken, we got nearly 45 Days of taken photos instead of 30, lately I’ve been reading it’s 30 Days and that’s it no additional 30 after first DOwnload and 45 Days is expiration on each photo to DOwnload unless you purchase extension.
Is this true???

My dilema is we are running a Share but I have two personal trips, can I still use the SAME MM if our trip starts on 3rd of Jan for 1 week (family), then we return on Feb 6th for 3 days (girls getaway)or do I need to join or make 2 shares?