how do I convert a short term rental to a full time rental in terms of depreciation?

It depends. You can take the first rental asset out of service, then enter a new asset for the full amount of the cost and indicate it was rented 100% of 2024 at fair rental value (FRV), assuming this is the case.

1. In the original asset indicate it was 'Sold, traded, etc..... then select either 'Special Handling' or it was converted to personal use when it comes up. This just stops the activity for this asset. Be sure to put the date removed from service.
2. Add the new asset that has become fully rental.
3. Keep the records for the depreciation you have already used on the property. It will be needed when and if you sell the property in the future. All depreciation will be recaptured at that time.