Is it just capped at a higher rate
It is capped in the sense that it is Asymmetric DSL designed to give a lower Up Sync, usually 888 K on Interleaved or about 1.1 - 1.2 Meg on Fast Path.
1999: Freeserve 48K Dial-Up => 2005: Wanadoo 1 Meg BB => 2007: Orange 2 Meg BB => 2008: Orange 8 Meg LLU => 2010: Orange 16 Meg LLU => 2011: Orange 19 Meg WBC