Are we supposed to be able to change an HTML INPUT tag's TYPE attribute?

For instance, we're doing this:

Original html:

```
<input type="text" />

```

And via jQuery, we change it to this:

```
<input type="number" />

```

This seems to work fine in iOS's Safari. Didn't occur to me it would be an issue.

But now we're seeing some issues on some Android devices and in doing some research, I'm finding mentions that some browsers do not let you change the type attribute at all for security reasons. 

The questions: 1) is this true? 2) If so, what, exactly, are the reasons for this? I can't figure out what kind of security issues this would cause if they allowed it.

UPDATE:

So far it seems that yes, it's true, but not due to any standard practice nor spec...just that some browsers don't like it. Namely IE and, I guess, some versions of Android browsers.