1. If you purchase 2 contracts at 2 different Home Resorts at the very same time directly from Disney they will get you same UY month, however, if one or both of the contracts are for " older " resorts it may take a bit of time for Disney to come through with these contracts ( there could be a waitlist for the particular resort(S) you are interested in etc. - - this is where Disney acquiring contracts through exercising their ROFR option comes into play - no doubt you have read about this here, their "buying back" contracts at
DVC resorts via the resale market ).
2. If you purchase 1 contract through Disney and then at a later date decide to acquire another contract at a different home resort through Disney ( ie, do an add-on directly with Disney ) again they will get you same UY month but again there could be wait involved as mentioned in #1. If you buy your
2nd contract via resale market at either same home resort as your first contract or with a different home resort it may be more difficult to find a contract with same UY month - but not impossible. It will probably take you longer through resale market to get same UY month than wait time for buying an add-on from Disney.
3. If you purchase your 1st contract via resale and then at a later date decide to acquire another contract at a different home through Disney or via resale market, again same as in #2.
FWIW, many members do have contracts with different UY's. It takes more 'coordination' but it definitely is not impossible to work with different UY's. It may be more beneficial actually depending upon if Contract 1 you are going to use for travel at a particular time of year and Contract 2 will be for travel at entirely different time of year - - then it may be preferable to have 2 different UY months because of banking deadlines.