Hi Paula, now that I have more information about your product, I can help you a bit more, unfortunately your product falls into the single serving danger zone and there's less wiggle room here than previously.
Your reference amount is 30g expressed as
_ cup (_ g) for small pieces (e.g., popcorn); _ piece(s) (_ g) for large pieces (e.g., large pretzels; pressed dried fruit sheet); 1 oz (28g/visual unit of measure) for bulk products (e.g., potato chips)
This is the "label statement" column of the RACC table which shows what the "common household measure" of your category is.
You still haven't told me what your product actually is/looks like, but based on your response I'm assuing it's a large discrete unit like a fruit bar or a rice cake?
70 grams of large pieces (pieces that couldn't be easily measured in a cup like pretzel sticks, fruit sheets, rice cakes)
In this scenario, your racc is still 30g, but you need to express it as the closest number of large pieces or portion of the container..
1. Weigh up several pieces and determine how many will get you closest to 30g (it may be just one).
2. Select the number of pieces that get you closest and get their weight. FDA's guidance says if a single unit weighs less than 50% of the RACC, the serving size should be more than 1 unit. Between 50-67% you can use one or two, if you're between 67-200% you must declare the serving size as the entire package. If you weigh between 200-300%, the serving size must be the proportion that approximates the RACC.
3. Express your serving size as X pieces (xg) where you use the actual weight of that many pieces to calculate your nutrition values. Or as entire container or 1/2 container as the rules in step two indicate.
Assuming your product is one discrete unit per package and it weighs 70g, one piece/container falls between 2-300% of the RACC. Under the old rules you would be fine following the steps above. But under the new labeling regulations you actually have to use dual-column labeling to list both the nutrition per 1/2 unit (35g) and the entire package (70g). (see section II.4 of the guidance you linked). Exemptions apply for the various compressed nut facts panels assuming you have low enough square In. of labeling to qualify.
Given that you're selling a snack item at <300% of the racc, you could make the argument that the average consumer is going to eat the entire package, just document that you believe it to be so based on your company's history with the product and I don't think you'll get into trouble.
Where you WILL get into trouble is if you're making front of package claims about protein content compared to competitors, but artificially inflating your protein by making your serving size larger. It's misleading to consumers because your product may not be more protein dense, but it's advertized as higher protein simply because the serving is large. Remember that RACC and serving size rules exist not only to help consumers do the math on their diet, but also to make sure that they can compare competing products to determine what the difference is on an apples-to-apples basis.
FDA has some enforcement discretion going on and explains how some people have gotten in trouble in that area.