Schema architecture and problems listening

Hey everyone.
Working on a tiny prototype, I'm running into a problem that I can't seem to solve on my own: Changes in state by the server are triggered when running the ser/client combo locally, but not when in production (with arena).

For the simplicity of it, think of it as a TicTacToe game with the following Schema

export class TicTacTwistState extends Schema {
	@type('number') gameState: GAMESTATE = GAMESTATE.WAITING
	@type('string') currentTurn: string
	@type('string') winner: string = ''
	@type({ map: Player }) players = new MapSchema<Player>()
	@type([BoardField]) board = new ArraySchema<BoardField>(
		new BoardField(0),
		new BoardField(1),
		new BoardField(2),
		new BoardField(3),
		new BoardField(4),
		new BoardField(5),
		new BoardField(6),
		new BoardField(7),
		new BoardField(8),

export class BoardField extends Schema {
	@type(Marker) marker: Marker
	@type('number') index: number
	@type('boolean') trigger: boolean = true

	constructor (index: number) {
		this.index = index

export class Marker extends Schema {
	@type('number') size: MarkerSizes
	@type('string') owner: string = ''
	@type('boolean') isLocked = false
	@type('number') color: number
	constructor (size: MarkerSizes, color?: number, shape?: MarkerShape, owner?: string) {
		this.size = size
		this.color = color
		this.owner = owner

I do understand, that this is like deeply nested, but would that in general cause problems? Is there anything I can do better here? If not, I'm wondering if the is the right way to listen to changes client-side:
	field =>
		(field.onChange = changes => {
			changes.forEach(change => {
				if (change.field === 'marker') {
//do stuff here

Weird thing is, that it seems to work locally, but once deployed, the whole (deep) board state does not trigger.

Thanks in advance for any ideas on this :) happy to provide more code if neccessary.

Is any errors shown in the logs?

@coco nope - everything smooth, it's just the client not getting a signal that has changed