I happen to know it. The Frequency Range of TL-PA4015PKIT is 2MHz - 67.5MHz.

To be more general :
.every "HomePlug AV" PLC use 2-28 Mhz (rounded) Frequency Range, with some exceptions going to 50 Mhz.
.every "HomePlug AV 2" PLC use 2-68 Mhz (rounded) Frequency Range, with some exceptions going to 86 Mhz.

There are notches (frequencies that are very attenuated) in this range in order to comply with other usages (amateur radio for example). They are defined in local regulations (In Europe see EN50561-1 for <30 Mhz and EN50561-3 for >30Mhz).
That's why you can see in the release note of your PLC firmware something like"Opening the function of EN50561".

Linky is another beast, it uses narrow-band PLC (CPL basse-fréquence) : less throughput, longer distance (like FM vs SW radio if you want a bad analogy).

On a side note, there is some known interferences between PLCs and VDSL2, but these are mostly (not always) seen in a Vectored VDSL2, which is not approved for use in France by ARCEP. Recent versions of tpPLC utility have an option to reduce these crosstalk interferences, at the cost of reduced speed between PLCs (no MIMO), but this should not apply to a 4-series PLC (SISO).