urgent- feral kittens need advice

We got a call the other day about a mom and her kittens living in a wood pile. Today, we went down there, trapped the mom, and hand-caught the kittens. I'm not 100% sure on the age of the kittens, but they appear to be anywhere from 4-6 weeks old. Could anyone give me good links to determining the ages of the kittens? They are walking and playing, and their ears have lost the round appearance, BUT they are not yet weaned. This leads to my question...
If the kittens are not fully weaned, even though they are at the sociable age, should I still go ahead with the original plan and TNR the mom cat? The original plan was to TNR the mom and put the babies into foster to be rehabilitated. I am scared that without the mom, they will not eat, and bottlefeeding feral babies is darn near impossible. Please, any advice would be helpful! I don't know what to do!

I checked some websites.

If the ears are "erect", that is a sign they are three weeks or older. Ditto with eyes changing.

They can begin to walk in a clumsy, wobbly manner at 25 days.

Have they grown baby teeth yet? Usually that is when the mamacat starts weaning them. Weaning should begin at four weeks of age.

Advice: Do you have a foster home where the mamacat and five kittens can be kept together for a few weeks? The mamacat could be spayed in a week (she's probably already pregnant again) and then released in a month. That would have given the kittens about eight weeks with their mother. Then the foster parents can keep the kittens together about another month to finish socialization and at around 12 weeks they would be big enough for early S/N and be adoptable.

I don't know if that is feasible or not.

If the mother has to be TNR'd immediately, the kittens could be fed kitten glop until they are ready for solid food. It might not require bottle feeding with KMR. (Do they have teeth?) I'd still give the kittens two months of fostering before trying to adopt them out.

Anyway, good luck and thanks for helping these cats. Don't know if my comments make much sense or not.