Calculating and compensating the group delay of filters, and channel models

Good morning, I am trying to use the channel models provided by GNU
Radio to simulate the behaviour of the BER. I read in this same forum
that symmetric filters have a group delay of (N-1)/2, where N is the
number of taps. This group delay avoid the samples to be shown, so it
seems they have been lost. I used the block “channelmodel” with only one
tap but the number of samples I cannot see is 8, the same happen with
other channel blocks such as “DynamicModel”.

My questions are:

1.Is there any way to determine the group delay in the channel models?

2.How can we compensate the group delay of the channel models, so we can
obtain the correct samples?

I really appreciate any help

Thanks

Hector