When trying to get between resorts, TTC should be your last option. Service from resorts to TTC tends to be sporadic.
Also, keep in mind there is no service from parks to DTD!
What I would do is keep moving forward.
If it’s daylight, grab the bus from your resort to Blizzard Beach and transfer to the resort you’re heading to.
If not, go to DHS for Epcot/Crescent Lake resorts.
MK for monorail resorts and for Wilderness Lodge.
Keep park closing times in mind, however during your stay, MK will be open well into the night while Epcot will close nightly at 9:30.
Buses continue to run about 90 minutes after that park closes.
Transportation does pretty much start at 7 AM because all parks have breakfast venues that open an hour before park open, although again, during Christmas week, MK opens most mornings at 8, so transport should start to MK at 6:30 AM.
Final tip, if you want to get to DTD from Epcot, walk out the International Gateway and head to the Beach. From MK, walk to the Contemporary and get the bus there. It will probably be much faster than taking the monorail to the Contemporary.