You have to do some thinking about this here. Were the pinks completely thawed when you received them? Are you or were you able to take the temp of them, when they arrived?
I am thinking of this, through my knowledge of food safety. I don't claim to be an expert, but I have had some previous training regarding this.
I see you are from England and I am not sure if you use or are familiar with Fahrenheit or Celsius. I am going to say everything in F and you may have to do the conversion. I am sorry for this.
OK, the food danger zone is from 41F - 140F. In this range, food begins to break down and bacteria begins to grow. You have four hours to do something, ie cook, freeze or refrigerate before the time expires. The only exception to this rule is cooking. If you wait the four hours, cook the food then allow it to return to the danger zone temps, you can add another four hours to the clock. That is the only thing that kills bacteria.
Freezing is another method. Problem is, this doesn't kill the bacteria, it slows or stops the growth. So, if you have a food item that was, lets say 100F for 30 mins and you place it in the freezer. Let's say that it takes 30 mins to freeze. Technically, you only have 3 hours remaining on the food safety clock.
I hope I am not confusing you.
So, with what you got, if you don't know the temps of the feeders when you received them, then it may be safer to dispose of them, rather then take a chance. You will have no idea, how long they have been thawed and at what temp they remained at, during shipping.
Now, if they were partially frozen, you should be able to safely return them to the freezer without worry. But, that is only if they were partially frozen, to reiterate. If the were just a little frozen, then you could place them in the fridge and maybe use them up in the next 2-3 days max.
Again, I hope I didn't confuse you. If there is something I wrote that needs clarification, please ask!
Wayne
Free