Roughly speaking, yes.
The UK will still leave but initially (30 March) relatively little will change. It heralds the start of a transition period where a lot of details need to be worked out. The initial proposal is that the UK would actually leave 'properly' at the end of 2020 assuming all the fine details have been discussed and agreed. The UK will continue paying into the EU for access to markets and so on but crucially will lose MEPs and any representation in the EU parliament. The UK would have to accept any rule changes but there may not actually be much that is altered anyway.
Everyone apart from Mrs May is unhappy about the WA for various reasons but it has been constructed so that nothing 'dramatic' happens. For the UK to get the best out of the WA it will have to negotiate skillfully, something that appears to be lacking over the last 2 years or more. A kind of amicable divorce. Since the magnitude of the intertwining of the UK and EU is only gradually coming clear the end of 2020 is looking over optimistic but as a catastrophic sudden 'no deal' scenario is avoided on 29 March is FAR preferable.
What happens with various industries will be exceedingly interesting, to put it mildly.