You can already get a t-34 before a p4. Most players choose a t-70 beforehand which is an optional investment and for obvious reasons delays the t-34.
I'm really tired of this myth that the p4 comes out earlier than the t-34 as it'd only be true if the t-34 is locked behind t-70, which it's not.
disclaimer: I'm omitting manpower cost, because I'm lazy and my spreadsheet is one patch out of date.
Phase 1 + Phase 2 = 145f. T1+T2+T3 = 30f. P4 is 120F. If you going for 251 or 222 - 30f on top. 325 with lights and 295f without. Ofc you can also skip t2 building, saving 20f more, but this is way too ballsy and quite hard, since shreks are unreliable.
T2+T3+T4 = 190f. If you add molly/at nade tech it is another 15f on top. T34-76 is 90f. At minimum you are paying 280F with T2. If you did not skip conscript tech - 295f.
I'd say that total cost is closer then it looks, but it is definitely possible to get t34-76 before OST gets its P4, but the difference is not as big as the difference in price between p4 and t34-76.
Correct me if I screwed up some numbers.