Can you castrate older boars?

Normally you would castrate males in their first week of life. At that time, it's really straight-forward and you can do it if someone teaches you how who has done it before.
We were going to keep these two boars for breeding, but decided we want to focus our pig energy on the Red Wattle breed mostly and may end up adding Berkshire to the mix next year.
We think that Duroc might have impregnated Scarlet, the larger Red Wattle gilt (the name for a female that has not had a litter) because he escaped the electric fence and was in the female pen for about 8 hours before we knew it.
Duroc will mature quicker, so he will be in the freezer this early winter. Mangalista takes longer, so more than likely he will be in early spring of 2024. Our Red Wattle boar, "Red" (Brian is so creative) will remain.