Toyo Proxes 94W vs 94Y

I've Toyo Proxes T1Rs fitted all round and the fronts need changing.

Rims are 225/45/17 and tyres are rated 94W but most outlets only offer 94Y - is it unwise to mix two Ys at the front with 2 Ws on the rear?

Also, to confuse matters further, the T1R seems to have given way to the TR1.

I prefer not to mix types or brands but don't know whether this difference is material enough...

The new Toyo Tr1's are way better than the old design, compound wears equally where as the old ones used to wear out quite fast when the tread depth reached around 5mm.

So could I put TR1 94Ys on the fronts while I still have T1R 94W on the rear?

I always fit new tyres on the rear when only fitting a pairs

Ok yes I tend to do that so I assume I'll be ok with 94Ys on the rear and the old T1R 94Ws on the front.

As long as I make sure the bonnet is properly shut