Can I kasher my meat oven and use it to cook dairy foods for Shavuot? 👀

So someone has one oven in their home and  it's used for Fleishigs. Now they want to   bake Milchig foods for Shavuot. What is the  best practice in order to use their Fleishig   oven to cook Milchig foods? If you can double  wrap your dairy foods, keep the oven Fleishig,   and make sure none of the Milchig leaks out of  the pan, then that is fine. That might be even   the easiest and best method. Otherwise, if you  need to bake it open, you need to kasher the   oven ahead of time. First, cleaning out the  oven, making sure that there's no residue,   no large stains of drips of meat in the oven.  Then waiting 24 hours after it's been cleaned.   Heating up the oven to the highest temperature.  Let's say 500°, 550° for an hour. Then you can   now use it for Milchig. Now, after cooking  Milchigs, you have to do the process again.   Make sure it's still clean. Okay? Hopefully,  nothing dripped and then it's clean. You wait   24 hours and then again you would burn out the  oven at 500 or 550 for an hour and now we could   go back to Fleishigs again. Now, this obviously  could take a lot of time. If a person wakes   up on Erev Shavuot and wants to start making  Milchigs, it's not going to be so practical.   Then you'll have to follow the first method of  making sure that everything is double wrapped.