llama 3.3 70b q4_k_m - tested on typescript with lots of generic constraints

I was testing llama 3.3 70b q4_k_m (llama.cpp commit b2f4a3e, rope_freq_base=500000, batch=512) on our typescript codebase yesterday, specifically on files with heavy generic usage - think utility types with 5-6 generic parameters that each have extends clauses and default values. The pattern I'm seeing is perplexity holds stable to around 20.1k tokens, then degrades noticeably (around 3.6% measured spike) when you have types like `Foo<T extends Bar, U extends Baz<T>, V = DefaultType<U>>` nested 4-5 levels deep. The model starts hallucinating constraint clauses that don't exist in the actual type definition. Anyone else seeing this with complex typescript generics? Wondering if this is a tokenizer issue with the angle brackets and commas or if it's a rope scaling problem at that context depth.