java.util.concurrent.RejectedExecutionException: Task rejected from java.util.concurrent.ThreadPoolExecutor

Upgraded to 18w43b earlier this afternoon. 2 users on wired LAN playing on server. Nothing else running on server, CPU and RAM usage very low. Snapshot extremely laggy. We see server overloaded messages spamming the console as well as player moved too quickly. After playing a few minutes (time varies each time), we get kicked with the message "time out". Looking at the console there are no more messages, like it's hung up or frozen. I had to close the console and reopen. After going through this 2-3 times, it finally crashed. I have attached 2 reports that were in the folder as well as all the logs from today.

18w43b\: [^crash-2018-10-25_18.21.31-server.txt]

---- Minecraft Crash Report ----
// Why did you do that?

Time: 10/25/18 6:21 PM
Description: Exception ticking world

java.util.concurrent.RejectedExecutionException: Task ud$$Lambda$1881/52634540@6c5559df rejected from java.util.concurrent.ThreadPoolExecutor@36e0d120[Terminated, pool size = 0, active threads = 0, queued tasks = 0, completed tasks = 193276]
	at java.util.concurrent.ThreadPoolExecutor$AbortPolicy.rejectedExecution(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor.reject(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor.execute(Unknown Source)
	at ud.a(SourceFile:105)
	at ud.a(SourceFile:63)
	at ty.a(SourceFile:352)
	at ty.b(SourceFile:587)
	at tz.a(SourceFile:177)
	at net.minecraft.server.MinecraftServer.b(SourceFile:724)
	at th.b(SourceFile:360)
	at net.minecraft.server.MinecraftServer.a(SourceFile:661)
	at net.minecraft.server.MinecraftServer.run(SourceFile:564)
	at java.lang.Thread.run(Unknown Source)


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Thread: Server thread
Stacktrace:
	at java.util.concurrent.ThreadPoolExecutor$AbortPolicy.rejectedExecution(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor.reject(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor.execute(Unknown Source)
	at ud.a(SourceFile:105)
	at ud.a(SourceFile:63)
	at ty.a(SourceFile:352)
	at ty.b(SourceFile:587)
	at tz.a(SourceFile:177)

-- Affected level --
Details:
	Level name: world
	All players: 1 total; [ub['chetisthedude'/303, l='world', x=-432.38, y=63.00, z=1982.44]]
	Chunk stats: ServerChunkCache: 3919
	Level seed: 8040780642136928405
	Level generator: ID 00 - default, ver 1. Features enabled: true
	Level generator options: {}
	Level spawn location: World: (-224,64,-160), Chunk: (at 0,4,0 in -14,-10; contains blocks -224,0,-160 to -209,255,-145), Region: (-1,-1; contains chunks -32,-32 to -1,-1, blocks -512,0,-512 to -1,255,-1)
	Level time: 50368477 game time, 51493331 day time
	Level dimension: 0
	Level storage version: 0x04ABD - Anvil
	Level weather: Rain time: 21442 (now: false), thunder time: 5381 (now: true)
	Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: false
Stacktrace:
	at net.minecraft.server.MinecraftServer.b(SourceFile:724)
	at th.b(SourceFile:360)
	at net.minecraft.server.MinecraftServer.a(SourceFile:661)
	at net.minecraft.server.MinecraftServer.run(SourceFile:564)
	at java.lang.Thread.run(Unknown Source)

-- System Details --
Details:
	Minecraft Version: 18w43b
	Operating System: Windows Server 2016 (amd64) version 10.0
	Java Version: 1.8.0_181, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 16837490656 bytes (16057 MB) / 17983602688 bytes (17150 MB) up to 47722266624 bytes (45511 MB)
	JVM Flags: 2 total; -Xms10G -Xmx50G
	Profiler Position: N/A (disabled)
	Player Count: 1 / 2; [ub['chetisthedude'/303, l='world', x=-432.38, y=63.00, z=1982.44]]
	Data Packs: vanilla
	Is Modded: Unknown (can't tell)
	Type: Dedicated Server (map_server.txt)