How can I update .Magnitude more effectively?

The titles a little vague, my apologies I didn't know how to word it. Basically, I'm creating a boss, and while the player is within 50 studs of the boss it will move towards the player constantly, this works fine as well as the attacks (I don't want to use pathfinding, so I'm using :MoveTo()). The issue is that when the boss respawns if the player is already within 50 studs the boss will sit there dormant. Here is the code I'm using to do this:

local Found = false
local B1 = false
local attacking = false

while wait(1) do
	
	local DBMpos = workspace:FindFirstChild("CaptainTennileImposter").HumanoidRootPart.Position
	local PlayerPos = game.Players.LocalPlayer.Character.HumanoidRootPart.Position
	local magnitude = (DBMpos - PlayerPos).Magnitude
	
	--Make sure he's alive
	if workspace:FindFirstChild("CaptainTennileImposter").Humanoid.Health > 0 then
		
		--If the players close then he'll move
		if magnitude <= 50 then
			if B1 then

				if (DBMpos - PlayerPos).Magnitude <= 5 then
					game.ReplicatedStorage.BossReps.DBMAttack:FireServer()
				end

			elseif not B1 then

				B1 = true
				game.ReplicatedStorage.BossReps.InDarkBlueMoon:FireServer(game.Players.LocalPlayer)

			end
		else
			B1 = false
		end
		
	end
end

I originally had it at wait() but it ran better to wait(1). What can I do to make it so that If the boss respawns and the player is within the 50 studs it will move? I have a print statement setup in the server side to detect when the player first triggers movement, but this doesn't fire when the player starts within 50 studs of the boss.