PHP numeric casing with goto

I pleasantly found that it is possible to use goto in PHP:

    case 222: return "A"; break;
	case 231: return "B"; break;
	case 234: goto 231;
	case 237: return "C"; break;
	case 251: goto 231;
	case 285: return "D"; break;

I have some code like this. There are a lot of keys that shared the same value, so I am trying to use goto to eliminate redundancy. I'm use a switch since it's simpler here than if/else branching.

For various reasons, each case must be explicitly defined as above, even if it just goes to another case. However, running this through a validator, I get Parse error: syntax error, unexpected ''231'' (T_CONSTANT_ENCAPSED_STRING), expecting identifier (T_STRING) in your code

I tried surrounding the cases with single quotes, but that still didn't pass. This seems in line with the example above. What am I missing syntax-wise here?

Label cannot be numeric only, so you could only solve it by creating extra label for cases you want to target (and also modifying gotos with those new labels):

<?php
function foo($value) {
    switch ($value) {
        case 222:
            return "A";
        case 231:
            label231: // new label here
            return "B";
        case 234:
           goto label231;
        case 237:
           return "C";
        case 251: 
           goto label231;
        case 285:
           return "D";
    }
}
var_dump(foo(251));

However as mentioned in the comments, I would prefer choosing a different approach (associative array etc.).