Changing prices via upload - Strange errors

I have a number of products in FBA that have been there for several years.

Recently I tried changing some prices via a Listing Loader file (something I have often done in the past) but I got these errors

Error 97777: The file you submitted cannot be used to change listings to Fulfilled by Amazon. You can only use Custom inventory files, XML feeds, and Inventory Loader or Listing Loader templates. If you are already using one of these, download the newest version and try again. [»]
Error 98888: ‘batteries_required’ is required but not supplied.

But I am using the latest Listing Loader template. However, looking at second error I thought is was because Amazon now require battery info for FBA items, so I entered FALSE under the batteries_required column and tried again. Now I get this error.

Fatal: The required sku field is missing from the file. To correct this error, download the template again and use the new copy, or insert the required field into your existing file. (90012)

But SKU is not missing and as already stated I am using latest copy of the file.

I sent request to CS and they came back to say, you guessed it, download latest copy of the template. I replied a week ago (by both phone and email) to explain I was using latest copy, but so far have had no reply

Can anyone here help?