Switching grammar tenses- past to present

In an indirect speech, there are two time frames. The main sentence (John explained), and the time of the original speech (go along..). As in direct speech, these time frames can be different. Your sentence is fine.
"Switching tenses" refers to changing the time frame of the main narrative.

John explained, "These are the reasons you should go along..."

Thanks. So it's only with a change in the time frame that switch in tenses is relevant? This is confusing as I am quoting in past tense so 'He said' with a direct quote. A sentence like the one above would come before it.

'He told me what we can expect of the show' I have also put 'expected' before. Which is correct?

And also

'Joe is directing the show and he explaine

'He told me what we could expect of the show. This change of tense in indirect speech is called "back-shifting." Sometimes we do it, and sometimes not.

The change in tenses can be avoided like this:
Joe, the director of the show, explained why it is significant to an audience.

Here is an example of incorrect tense-shifting:

Jane went on her usual walk to the

I see, thank you. You say that backshift doesn't always need to be to be used. In my example above, could I still use 'can' as the show is happening in the future. Ie. It's upcoming rather than it has already happened. Or just stick with 'Could'?

As I'd like to keep it as explained. However, I do know that explain would be more consistent. If use 'Can' would that make it grammatically inc