well ive never recorded an exact temperature change, however i would think figuring the temperature would be fairly simple. so you have to boil your oats for an hour prior to adding to your grist weight. well youll have to protein rest the oats, so youd want your grist temp to be 122F. so you can figure that if you were to calculate out the rest of your grist and strike temp to have a temp of 122, then youd just cool your oats with the boil water to 122 in an ice bath and add it to your grist and rest it, then decoct the liquor and raise the temp to your desired strike temp to mash.
ok lemme give an example. say youre going to use 10 lbs of grain not including your oats. you want to rest it at 122F. say youre desired mash thinckness is 1.25 qt/lbs. say your tun and grain temp is 70F. you would want to add roughly 8.5 quarts of water at 212 (boiling) to your tun, then stir in your 10 lbs of grain. in the meantime you would have your oats and boil water for the oats cooled to 122F. already. then you would just add that and mix, then rest for 30 minutes, decoct, raise temp, so on and so on. of course, the amount of strike water would depend on your batch size as well. this is a link to a calculator that can be used to make your figuring very simple. Mash and Sparge Water Calculator ::: Brew365 - Homebrewing Recipes and Articles
. hopefully that helps.