Soft eggs!

Hi all, I'm new to the whole country lifestyle so wanting a bit of advice.
We got ourselves a couple of chickens for calf club and they've raised up beautifully and now been laying for about 4 weeks. The problem is they are laying a lot of soft eggs and multiple eggs a day which of course are not hard shelled at all. It happens probably every second day between the two of them and they are laying good eggs the rest of the time. It's like their hormones are in overdrive and producing too many eggs at once so they aren't having time to process through the body properly.
Will this settle down as they are still young or is there a prob with them or environment or food etc?
Any ideas?
They are fed commercial layer feed with some grit mixed in and every couple of days they get some veg and cereal scraps. They are free ranged for most of the day (after laying -if they do!).
Any help would be much appreciated.

it can take a while for new pullets to settle down. Often the time you get double yolkers too. Lose the grit from their feed and have it available on the side so they can use it only if they need it. Having it mixed with the feed can cause all sorts of problems long term. Are they both doing the multi egg thing or just one of them?

Thanks.
I believe it is both chickens laying soft eggs and yes we've had a couple of double yolks which was exciting for the kids!
How long would I expect for them to take to settle down with their laying?

Double yolkers sound great, but the 2 hens I have that consistently laid double yolkers got prolapses When the first one happened I managed to push it back with some preparation H as recommended by Dr Google, but as soon as she started laying again it all came out, so unfortunately she went for the chop. As soon as the second one prolapsed, I didn't try to treat her and just went straight to plan B, so keep an eye out.