These redundancy codes are used when you are amplifying a sequence that has a polymorphism under the primer. So some organisms or individuals may have an A base at a position and other organisms or individuals have a C base at the same position. If you want to amplify both sequences from everyone then you need a primer with both T and G at the same position. This is not possible so when you ask the company to make a primer with a redundancy they will make 2 oligos one with T and one with G at the position. You will get 2 different oligos in the same container and when you use the oligo you will know that it will anneal to both sequences in your dna sample.. In your example you will have at least 8 different oligos in your synthesis but just use it as one oligo and it will work on all of the expected sequences. Primers in pcr are in great excess so do not worry about having less of each sequence the mix of primers will work if you treat it as just one oligo.

your primer provider will produce all combinations, so that you'll be able to use these primer to amplify your target.

keep safe

fred