I love the 4G coverage on the Jubilee line, it's absolute great. I assume the gaps in the 'end of spring' coverage between Woolwich and Custom House are under

I love the 4G coverage on the Jubilee line, it's absolute great. I assume the gaps in the 'end of spring' coverage between Woolwich and Custom House are under the river and the two places the train surfaces (where it wouldn't be needed)?