//..the uk is a signatory to both of these documents.//
Yes I know that. But if we're quoting international law, I also know that the Article 31 of the 1951 Declaration which you cite says this:
"The Contracting States shall not impose penalties, on account of their illegal entry or presence, on refugees who, **coming directly from a territory where their life or freedom was threatened** in the sense of Article, enter or are present in their territory without authorization, provided they present themselves without delay to
the authorities and show good cause for their illegal entry or presence."
Nobody who enters the UK from France is coming "...directly from a territory where their life or freedom was threatened." So, by implication, if the receiving State cannot impose penalties on those who do arrive directly, it should be legitimate to impose penalties on those who don't.
However, that is somewhat by the way. The vast majority of arrivals from France are not asylum seekers. They are economic migrants. In particular, those from Albania have no grounds whatsoever to seek asylum. Albania is a peaceful European country and a candidate nation to join the EU. The government should state this as a fact and demonstrate that it will not entertain any asylum claims made by Albanians. They should be returned to Albania immediately.
However, a bit wider than that, the declarations you cite are over seventy years old and are no longer fit for purpose. It is preposterous that any nation should suffer an influx of up to 1,000 migrants a day and be expected to feed and accommodate them on demand. It is interesting to compare the treatment that illegal migrants to the UK receive with that meted out to those intending to invade the Spanish enclave of Melilla in North Africa:
https://www.reuters.com/world/africa/hundreds-migrants-storm-spains-melilla-enclave-2022-06-24/
This was just four months ago and, as far as I can recall, was not widely publicised in the UK. The Spanish are also signatories to the Conventions you cite. But they clearly viewed this an illegal invasion of their territory. It is no different in principle to those trying to enter the UK by boat but the approach taken is vastly different - and far more appropriate.
It is clear that the UK cannot sustain an influx of homeless migrants at the rate currently taking place. If the UN Conventions say that it must, then it is time for the UK to consider its position with regards to those conventions.