I'm so sorry that Albert hasn't come home yet, it must be just awful
for you.

Our first cat, Jasper, would disappear every year or two and stay away
for 6 months. There was no reason obvious to us for these absences but
we would see nothing of him for months and then he would turn up, eat a
whole can of food and settle down in the most comfortable chair to be
fussed over and adored. He did differ from Albert in that he was not an
indoor cat and was a bit feral (long story). However, he survived alone
in the bush all that time and I don't think he was with anyone else
because we lived in a small community and if any had him they would
have told us.

I hope this helps. All cats are different but it is not unheard of for
them to return after long absences. I hope Albert is one of them.

All the best
Kate