The defenders at the fortress... what should we do with them?

basically, I end up trying to take a Castle with a 1 growth rate when I have a 1.5 growth rate, and with these defenders, I have no chance.

And they would have been defeated long ago if it weren't for their high defense, and if I'm not mistaken, they are immune to defense reduction.

Thus, my super-upgraded ballista behind Vittorio only takes out 36 of these defenders.

There's also another downside: we're playing against the clock (and again, "huge thanks" to whoever came up with the idea of including battles, especially battles between players, in the overall limited time), so after the battle, leaving the hero with only the defenders, he goes to the tavern, and I can't take the empty Castle with a secondary hero because the turn has passed.

I understand that they wanted to protect against the simple tactic of entering a battle and wasting time, but there's such a wonderful thing as a dynamic battle; 20 seconds is enough to think about actions (although I would increase it to 40, because due to my lack of experience, I have to learn about magic and creature properties right during the battle).

I hope that in 3.1 they will remove the dependence of the defenders on the month; otherwise, the possibility of the opponent winning at approximately the same level of play is excluded. :(

p/s Since I was counting on winning in the open field, I developed my hero towards light magic and the ballista.

p/p/s I hate dwarves, their runes, and all their other stuff; in every battle, the dwarf's troops either double-attack or reach my troops on the first try, or they do all sorts of other nonsense...

Added 3 minutes ago

I hope that in 3.1 they will remove the dependence of the defenders on the month; otherwise, the possibility of the opponent winning at approximately the same level of play is excluded.

or did the developers think that the dwarf would sit without venturing out for 12 months, and therefore they needed to provide him with self-developing defense?