@naka yes, that's what TLK is supposed to mean, IC and TLK are pretty much the same mostly, besides rolling stock, IC is modernised/new rolling stock and TLK is old rolling stock
@naka if you check bocznica.eu and type TLK, there's still quite a lot of them (besides the nameless international ones which are just night trains to Ukraine on broad-gauge), though some are using old german DMUs because of constant diesel loco shortage(seen when typing in SN84)