Plusnet/EE different network strength?

[#1]

TL;DR   Is it normal that plusnet and EE reception is different?

Hi all, 
I am currently on O2 and have no reception inside my house, although I have wifi calling, I don't get SMS messages. I have got sim cards from each of the other networks to test, and EE was the best giving me 2-3 bars. Vodafone gave me nothing,  3 gave me 1 bar.  I am intending to switch to EE based on this.

However someone who has a Plusnet mobile phone was visiting me, and in exactly the same location that my test showed 3 bars of EE, he got nothing. No signal. He suggested that Plusnet don't get the same signal strength as EE, but I don't understand that. I get the piggyback providers may not get the full features of the parent network, but not that the masts can somehow filter like this. Does anyone know more?

thanks 

Rob

[#2]

Same answer as on EE, PN do not have access to the 800Mhz band.

[#3]

Plusnet mobile do not have access to the EE 800Mhz 4g band (Band 20) so 4g signal strength could well be different in some locations