Cracking Brickwork

[owner2019]

I have been in my new build house now for approx 3 months and have noticed several cracks developing on one wall. The developer is trying to say this is just down to weathering and shrinkage but I am concerned that there might be more to it. It seems strange to me that you would get a vertical crack straight through 11 or so bricks at the exact same place on each side of wall (top right/left).

Further to this there is a clear difference in the bricks/mortar that has been used at the bottom of the house to the top of the house, several bricks which have been badly chipped have already been removed and replaced too. I have finally managed to get them to agree to an independent building surveyor to inspect the brickwork but I am still worried that I might have a bigger issue on my hands.

There appears to be effluent coming out of the drainage plugs in the bottom half of the house too which they have said is just driving rain getting into them and draining out rather than there being any water in the brickwork.

Pictures attached.

[New Home Expert]

Who is the housebuilder?
Why do buyers post without naming the housebuilder. It can have a direct bearing on the answers given!

Firstly, the weep vents at cavity trays and lintels do drain water that gets in the brickwork. The staining is cement or lime in the mortar droppings on the cavity trays and/or efflorescence.

The vertical cracks are of a concern, especially those that go through a brick such as in the last photo.
Is there any cracking internally?  It does look like some sort of subsidence or heave.
Write (not telephone - you need  a written record!) to both the housebuilder and warranty provider straightaway.

[owner2019]

The builder is Persimmon Homes.

We have since had a defect survey report carried out, which has stated that the following needs done:

Installation of bed joint reinforcement as per the guidance stated in section 5.1 of the report and prepared by Premier Guarantee
Replacement of all fractured bricks to the gable corners
Raking back and repointing of the isolated hairline fractures to mortar
Installation of a vertical movement joint between the french door head and first floor window sill, extending above the first floor window head, to eaves level

I wrote to the managing director and all of a sudden they are interested in fixing the issues.
We havent noticed any cracking internally in those areas as far as we can see.

[New Home Expert]

As there is no internal cracking it could just be a need for movement joints in the brickwork.
It also seems Premier Guarantee warranty has already noted the walls were not built to specification anyway.

Good luck dealing with both Persimmon and Premier Guarantee!