Marking before heat cycle

Hoping to get advice from those with intact bitches.

Kis is peeing in the house again - in front of the tv, as she has done before. She's done it twice today alone. She is overdue for a heat cycle so I'm wondering if the marking in the house is related to her being intact and it's worsening with the hormones. I'm ready to throttle her - should I be putting pants on her - she's so quick I don't catch her doing it. In the meantime, she still doesn't pee on walks.

And not really a question, but I noticed from previous heat cycle that Kis gets skittish before she goes into heat. Then when she goes into heat she gets more confident.

She will be spay now she is not being shown, research last year suggested avoiding between 1-2yrs of age. But if spaying fixes the peeing in the house maybe we should go earlier (she also needs a tooth out).

 

I wasn't planning on desexing until she was 2 as I expected to show her. Now I'm just waiting for Tully to get better. Kis also needs a tooth removed so I figured I'd do both surgeries together. That research last year found in Shelties UTIs were more common in bitches spay between 1-2 years. I don't have a problem with waiting until she is 2 yrs - but the peeing on the carpet every day is driving me nuts. She's not showing any signs of a UTI, bit too broke atm thanks to vet bills.