How could the Malachim have appeared to Avrohom on Pesach and Yitzchok was also born then? [closed]

Rashi says that It was Pesach when the Angels appeared to Abraham and informed him of the upcoming birth of his wife Sara. The Gemoro says that Yitzchok was born on Pesach exactly a year later. That means he was born 354 days later. How then did the Angle make a scratch on the wall and said at this time next year when the sun reaches this exact spot again you will have a child. The sun takes 365 days to return to its spot and he was born only 354 days later?

The Chasam Sofer notes that there seems to be a contradiction between the posuk and the Midrash quoted by Rashi. On the one hand the angel told Avraham that he will return to him next year at this exact day and time. The date was Pesach. Exactly one year later on this day would also be Pesach. On the other hand the angel made a mark on the wall to indicate where the sun would shine. The simple understanding is that the angel made a mark where the rays of the sun were shining on that day and said that when the sun returns and shines there again, he will return and Yitzchak will be born. The problem is that these two times are not the same. The day the sun would return is dependent on the solar year which is 365 days, whereas next Pesach is dependent on the Jewish lunar year which is 354 days. There is an eleven day difference. The Chasam Sofer answers that we have no choice but to assume that the mark that the angel made was eleven marks distant from where the sun shone that day. In other words, every day the sun casts its rays slightly higher or lower than the previous day. Thus the mark of eleven days from now would be eleven marks higher or lower on the wall.

I can prove that SJR answer is right and it is not a Dochek to learn Pshat that he made a sign for a later time. By King Pharoah Moshe Rabbeinu made a sign on the wall and said that 'tomorrow the plague will be gone'. If his sign was for that day, then it takes 365 days to reach that point again. So you could learn that it reaches the same point every day and Pharoah said at this time tommorow and the Malach meant at this time in 354 days. But I dont think it true scientifically. So he must have made a scratch for a later date, one day later. So too by the Malach, only for 365 - 11 days later.

I can think of 2 possible scenarios. Either he made a mark 11 days off or he returned 3 days after Yitzchok's Bris.