What extended BFing link are you referring to that sounds like you shouldn't BF after 3? I need to check that out. You can definitely BF for as long as you and your LO wish to.
Many BF LOs do not make it to 4hrly feeds at 4mo or even 6mo so if feeding 5 times in the day is working for you i would keep that up. EASY is just a guide, you don't have to make your baby's routine fit it perfectly. I never topped up after solids but offered water in a sippy cup as a drink.
I think most mums love BFing, especially after the early weeks when it gets easier for most of us. It is a wonderful thing to do and creates a very special bond so I'm sure you would love it even without being a single parent
If I've missed any of your BFing queries please let me know.
ETA, you can offer cows milk after 1yo but you don't have to. Breast milk is better for them.
I only dropped feeds as we dropped naps. They did get a little shorter at some points in the day when LO was less hungry as solid food increased. i let baby lead on that one as long as it wasnt too early in the first year.
So for example when Ds1 was 1yo we were doing something like
8.00 WU BF
09.00 solid breakfast
11.30 solid lunch
12.30-3.30 nap
3.30 BF
5.00 solid dinner
7.30 BF
8.00 BT
DS2 was still on 2 naps (and lower sleep needs) so it was more like
6.30 WU BF
8.00 solid breakfast
10 BF
10.15-11.45 nap
12.00 solid lunch
2.00 solid snack (fruit)
2.30 BF (sometimes this was after nap 2 if we were out and he fell asleep, later we sometimes skipped it)
3.00-3.45 nap
4.30 or 5.00 solid dinner
7.00 BT BF
7.30 BT
It wasn't exactly those times every day of course and depended on what we did and where we were etc. But the general order was as above.
As they got older we replaced the day time BFs with a solid snack like a yogurt or fruit and just did the morning WU and BT BFs. We dropped the morning WU BF around 24 or 25mo and then dropped the last feed at BT at 26mo for both of them.
HTH