This is why I posted an article with links to Kodak and Ilford technical publications. Best to go to the source.
Regarding D-76, the only comment Kodak makes is that when diluting it 1+1 if bubbles form you should let the solution stand for a few minutes to let bubbles dissipate.
For ID-11 (same as D-76), Ilford says once it cools to the working temperature it is ready for use.
Regarding XTOL, in fact Kodak makes a point of saying:
• Convenient, room-temperature
mixing for immediate use